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Carburetor Owners Manual

1. eese 22 23 WARRANTS s eee eti es een dem 23 EDELBROCK CARBURETOR DATA LOG ENEE 23 SECTION 1 THEORY OF OPERATION BASIC ENGINE REQUIREMENTS The spark ignition 4 cycle engine burns a mixture of AIR and FUEL The air is controlled by the driver s operation of the throttle The fuel is mixed with the incoming air by the carburetor The Ratio of AIR to FUEL is the AIR FUEL Ratio A F This is a ratio by WEIGHT if 12 pounds of Air are combined with 1 pound of Fuel the A F is 12 1 or more commonly A F 12 Despite the enormous variety in engine designs virtually all spark ignition 4 Cycle engines have very similar A F Ratio requirements For fully warmed up engines the range of A F is A F RATIO CHARACTERISTICS 5 RICH BURN LIMIT Combustion is weak erratic 6 9 EXTREMELY RICH Black smoke and low power 10 11 VERY RICH Some supercharged engines run in this range at full power as a means of controlling detonation 12 13 RICH Best power A F Un supercharged WOT 14 15 CHEMICALLY IDEAL At 14 6 the A F is at the theoretical ideal ratio with no excess fuel or oxygen after combustion Good A F for part throttle cruise and light to moderate acceleration 16 17 LEAN Best economy A F ratio Borderline for part throttle drivability worse than borderline if EGR is used 18 19 VERY LEAN Usual lean limit Driveability 20 25 LEAN BURN LIMIT Varies with engine Lean 17 0 and system Even though engines will
2. 1409 Calibration Reference Chart Primary Metering Step 1 Select the combination of Cruise Mode and Power Mode fuel metering stages desired for Power Mode Low Vacuum High Power Rod Up i d d 3 stages 2 stages 1 stage Base Power 1 stage 2 stages 3 stages your calibration Normal calibration changes Lean 12 Lean 8 Lean 4 Mode Rich 4 Rich 8 12 will be within the shaded diagonal area That is Cruise and Power mode changes should be in e 3 the same direction either richer or leaner and 3 stages 3 usually by the same amount E Rich 12 2 Step 2 Find the number that is nearest your desired JI 2stages combination This is your Calibration 2 Rich 6 Reference Number 2 gt 1 stage Step 3 Find the Calibration Reference Number you have E Rich 4 3 just selected in Step 2 Listed will be the Main Jet a z and Metering Rod required to achieve the desired 5 Mode E fuel metering for the Primaries 5 5 gt 1 stage Q Lean 4 E T 2 stages 4 Lean 896 Stock Calibration 2 s 2 Lean 12 3 oO using Calibration Kit 1488 plus the stock jets and metering rods Numbers in white are the steps obtainable using jet and rod combinations shown on this page Numbers in black are the steps obtainable Lean Power Mode gt Rich Model 1409 ROD JET REFERENCE CHART Secondary Metering MAIN JET METERING ROD CHANGE FROM BASE The factory calibration jet
3. e Stock Calibration 3 stages 5 E Lean 1296 3 Q 1452 070 x 052 Rod amp Jet 1457 073 x 052 1456 073 x 047 1454 073 x 037 1445 065 x 047 Rod amp Jet 1444 065 x 037 Rod amp Jet 1449 070 x 037 Rod amp Jet 1447 068 x 047 Rod amp Jet 1456 073 x 047 Rod amp Jet 1454 073 x 037 Rod amp Jet Model 1407 amp 1410 ROD JET REFERENCE CHART SECONDARY METERING METERING ROD CHANGE FROM BASE The factory calibration jet is shown in the center column For leaner or richer calibration use the jet indicated in the 1453 071 x 047 appropriate column 1433 113 070 x 042 1433 113 070 x 037 ve 3 Stages Lean 12 JET 1427 098 1434 116 073 x 037 2 Stages Lean 8 JET 1429 101 1431 107 063 x 047 d 1432 110 u 065 x 047 1 Stage Lean 4 JET 1430 104 1452 070 x 052 SECONDARY Stock Calibration JET 1431 107 1441 062 x 0527 1 Stage Rich 4 JET 1432 110 1447 068 x 047 Garg 1443 063 x 047 3 Stages Rich 12 JET 1434 116 1445 065 x 047 1453 071 x 047 1449 070 x 037 Main Jet D All Edelbrock jets have 120 prefix The 1443 063 x 047 last three digits minus 300 actual jet size 1442 063 x 037 Examples 120 398 098 jet Edelbrock p n 1427 EH men 120 413 113 jet Edelbrock p n 1433
4. 1432 110 1449 070 x 037 1432 110 068 x 057 1432 110 1448 068 x 052 1432 110 1447 068 x 047 1432 110 068 x 042 1 1433 113 073 x 042 1412 amp 1413 Calibration Reference Chart Primary Metering Step 1 Select the combination of Cruise Mode and Power Mode Low Vacuum High Power Rod Up Power Mode fuel metering stages desired for A 3 stages 2 stages 1 stage Base Power 1 stage 2 stages 3 stages your calibration Normal calibration changes Lean 12 Lean 8 Leen 4 Rich 4 Rich 8 Rich 12 will be within the shaded diagonal area That is Cruise and Power mode changes should be in 2 the same direction either richer or leaner and 3 stages 5 usually by the same amount e Rich 12 24 Step 2 Find the number that is nearest your desired 2 stages combination This is your Calibration z me Reference Number 0 A stage 2 Rich du 2 Step3 Find the Calibration Reference Number you have 3 E just selected in Step 2 Listed will be the Main Jet B Bice Power gt and Metering Rod required to achieve the desired S Mode 2 fuel metering for the Primaries 3 gt 1 e o Lean 4 E T 2 stages E Lean 8 e Stock Calibration 2 3stages amp Lean 12 9 4 m Wi using Calibration Kit 1480 plus the stock jets and metering rods Lean gem Power Mode gt Rich Numbers in white are
5. High Altitude Altitude has a direct effect on the operation of most carburetors As the altitude increases the air becomes less dense so a carburetor originally calibrated at low altitude delivers too much fuel and the engine runs richer If the preceding tuning procedure is performed on an Edelbrock Performer Series carburetor a proper high altitude calibration will result If the vehicle was Calibrated at lower altitude however and is to be driven at high altitude temporarily it is not necessary to repeat the complete calibration procedure Instead use the rule of 2 leaner per 1500 feet and the Calibration Reference Chart for your model carburetor For example with a 1405 at baseline calibration location 1 on the chart and intended operation at 6000 ft altitude you would want 6000 divided by 1500 x 2 8 leaner calibration That would be location 24 on the chart which would require only a rod and jet change Blended Fuels Typically two types of blended fuels are available Gasohol and gasahol Gasohol is a blend of not more than 10 ethanol and gasoline As long as there is no more than 10 ethanol mixed with the gasoline you carburetor will function properly As the percentage of ethanol climbs above10 a richer A F ratio will be required Also because gasohol is more volatile than gasoline hard hot starting and poor hot weather driveability may result Gasahol can be a blend of either ethanol methanol or other alco
6. 098 1428 100 1427 098 1428 100 1428 100 1430 104 1430 104 1427 098 1429 101 1430 104 1430 104 1426 095 1427 098 1428 100 1428 100 1427 098 1428 100 1427 098 1426 095 1427 098 1427 098 1430 104 1430 104 1428 100 1430 104 Model 1405 ROD JET REFERENCE CHART METERING ROD 1451 070 x 047 Some Have ID 695 1450 070 x 042 1449 070 x 037 1458 075 x 037 1448 068 x 052 1452 070 x 052 1445 065 x 047 1448 068 x 052 1446 068 x 042 1459 075 x 047 1455 073 x 042 1441 062 x 052 1448 068 x 052 1457 073 x 052 1456 073 x 047 1445 065 x 047 1452 070 x 052 1451 070 x 047 Some Have ID 695 1450 070 x 042 1445 065 x 047 1452 070 x 052 1457 073 x 052 1455 073 x 042 1457 073 x 052 1459 075 x 047 1449 070 x 037 1446 068 x 042 1456 073 x 047 1455 073 x 042 1458 075 x 037 CHANGE FROM BASE none stock calibration Rod amp Jet Rod amp Jet Rod amp Jet Rod amp Jet Rod amp Jet Rod amp Jet Rod amp Jet Rod amp Jet Rod amp Jet Rod amp Jet Rod amp Jet Select the combination of Cruise Mode and Power Mode fuel metering stages desired for your calibration No
7. PERFORMER SERIES amp THUNDER SERIES AVS LARBURETOR OWNERS MANUAL Edelbrock Corporation 2700 California Street Torrance CA 90503 Tech Line 1 800 416 8628 n 01185 34710034 18 o Rev 09 05 www edelbrock com Au parts not legal for sale or use on pollution controlled vehicles Brochure 00341 Raw 63 0062 2005 Edelbrock Corp INTRODUCTION Your Edelbrock Performer Series carburetor was calibrated using Edelbrock Performer Performer RPM and Torker Il Power Packages The carburetor metering was developed on Edelbrock engine dynamometers chassis rolls and a variety of development vehicles Although in most applications you will not need to recalibrate your carburetor you may wish to change the factory calibration to best meet any unique needs of your engine The following manual consists of 2 sections Theory of Operation and Tuning Procedure Upon review of Section 1 Theory of Operation you will be prepared to develop your own individualized calibration Section 2 Tuning Procedures will take you through a step by step procedure that will enable you to achieve a desirable calibration For added ease of tuning a Calibration Reference Chart for your model of carburetor has been included TABLE OF CONTENTS SECTION 1 THEORY OF OPERATION sesenta 2 BASIC ENGINE REQUIREMENTS eren 2 METERING SYSTEMS 2 1 NIE 2 2 Primary Main EG 3 3 Secon
8. Note that some later model vehicles the 5 0L Ford is one example have mechanical pumps that will give more than 6 0 psi at idle The vehicle will perform well but may be prone to stalls on quick turns and stops with the clutch disengaged If this problem occurs check the fuel pressure If it is more than 6 0 psi at IDLE it should be reduced through the use of a regulator such as Edelbrock 8190 or by creating a restricted by pass bleed to the fuel return line Edelbrock Street Fuel Pumps are highly recommended for all Edelbrock Performer Series carburetor installations Always use a filter such as Edelbrock 8873 between the pump and carburetor Note that a good filter is large in area so it may be able to transmit a significant amount of heat to the fuel It is a good practice to keep the filter away from heat and not allow it to come in contact with part of the engine Air Cleaners Your Edelbrock carburetor was originally calibrated with a low restriction open element air cleaner configuration a 14 x3 Edelbrock Signature Series unit It was also evaluated for proper metering and vehicle performance using a variety of other air cleaner designs and will perform as intended with nearly any reasonable air cleaner design While the Edelbrock Performer Series carburetor does not exhibit excessive sensitivity to the air cleaner there are several guidelines you should follow when selecting an air cleaner Running without an air cleaner is s
9. time the secondary is in the transient phase This is accomplished by placing a small Discharge Nozzle 2 at a point just under the Air Valve 1 The air flow past the edge of the Air Valve creates sufficient pressure drop to pull fuel out of the Auxiliary System The fuel must first pass through the Secondary Main Jet 3 to the Secondary Well it is then drawn through the Auxiliary Fuel Tube 4 and exits at the Discharge Nozzle 2 There is always an air bleed either in the Auxiliary Fuel Tube near the top or as a separate brass restriction bushing shown 5 Air Bleed some PNs 2 Discharge Nozzle The flow of fuel in the Auxiliary System is enough to prevent a lean transient on Secondary opening As the Air Valve is opened further by increasing air flow the fuel flow through this system decreases Correspondingly the fuel flow in the Secondary Main System increases providing a near constant A F Ratio en 3 Secondary Main Jet 4 Au 1 Air Valve uxiliary Fuel Tube SECONDARY AUXILIARY SYSTEM FIGURE 6 Pump System When the throttle is opened rapidly the air flow through 3 Pump Jets the engine will increase immediately The fuel since it is much heavier than the air will lag behind This contributes to a temporary lean A F condition Regardless of cause a solution is to temporarily enrichen the A F Ratio PUMP SYSTEM by mechanically pumping a small quantity of fuel
10. 063 x 037 1434 116 1444 065 x 037 1432 110 1452 070 x 052 1433 113 1457 073 x 052 1433 113 1456 073 x 047 1433 113 1454 073 x 037 1431 107 1445 065 x 047 Rod amp Jet 1431 107 1444 065 x 037 Rod amp Jet 1432 110 1449 070 x 037 Rod amp Jet 1431 107 1447 068 x 047 Rod amp Jet 1432 110 1456 073 x 047 Rod amp Jet 1432 110 1454 073 x 037 Rod amp Jet 1434 116 1449 070 x 037 1805 1806 Calibration Reference Chart Primary Metering Power Mode Low Vacuum High Power Rod Up 3 stages 2 stages 1 stage Base Power 1 stage 2 stages 3 stages Lean 12 Lean 8 Lean 4 Mode Rich 4 Rich 8 Rich 12 Cruise Mode High Vacuum Low Power Rod Down d mk Ph H 10 11 2 Seis 14 3 17 8 9 3 stages Rich 12 2 stages Rich 8 1 stage Rich 4 Base Power Mode 1 stage Lean 4 2 stages Lean 8 3 stages Lean 12 14027 098 1436 068 x 057 1427 098 1456 073 x 047 1425 092 1444 065 x 037 Jet and Rod 1426 095 1426 095 1452 070 x 052 1427 098 1419 075 x 047 Lean gn Power Mode gt Ri
11. 070 047 orange 5 0935 7 16 1 middle hole 1 3 16 1 9 16 1 7 16 1 11 16 075 047 yellow 4 0935 7 16 middlehole 1 3 16 1 9 16 1 7 16 1 11 16 071 x 047 orange 5 0935 7 16 1 top hole 1 7 16 1 9 16 1 11 16 1 11 16 068 047 orange 5 0935 7 16 middlehole 1 3 16 1 9 16 1 7 16 1 11 16 071 x 047 orange 5 0935 7 16 1 top hole f 1 7 16 1 9 16 1 11 16 1 11 16 075 047 orange 5 0935 7 16 top hole 1 1 7 16 1 9 16 1 11 16 1 11 16 071 x 047 orange 5 0935 7 16 top hole 1 17 32 1 5 8 1 3 4 1 3 4 071 x 047 orange 5 0935 7 16 top hole d 1 17 32 1 5 8 1 3 4 1 3 4 Carburetor is certified to meet U S Coast Guard Requirements Select the combination of Cruise Mode and Power Mode fuel metering stages desired for your calibration Normal calibration changes will be within the shaded diagonal area That is Cruise and Power mode changes should be in the same direction either richer or leaner and usually by the same amount Step 1 Step 2 Find the number that is nearest your desired combination This is your Calibration Reference Number Find the Calibration Reference Number you have just selected in Step 2 Listed will be the Main Jet and Metering Rod required to achieve the desired fuel metering for the
12. 092 1445 065 x 047 1426 095 1451 070 x 047 Rod amp Jet 1426 095 1446 068 x 042 Rod amp Jet 1427 098 1455 073 x 042 1427 098 1456 073 x 047 1427 098 1454 073 x 037 1407 1410 Calibration Reference Chart Primary Metering Step 1 Select the combination of Cruise Mode and Power Mode Low Vacuum High Power Rod Up Power Mode fuel metering stages desired for 3 stages 2 stages istage Base Power 1 stage 2 stages 3 stages your calibration Normal calibration changes Lean 12 Lean 8 Lean 4 Mode Rich 4 Rich 8 Rich 12 will be within the shaded diagonal area That is Cruise and Power mode changes should be in the same direction either richer or leaner and Numbers in black are the steps obtainable e using Calibration Kit 1480 plus the stock jets and metering rods Lean n Power Mode gt Rich Numbers in white are the steps obtainable using jet and rod combinations shown on this page g es E usually by the same amount Step 2 Find the number that is nearest your desired x 2Stages doe TP S Rich 8 combination This is your Calibration 2 Reference Number 1 sti 4 Rich 3 Step 3 Find the Calibration Reference Number you have d just selected in Step 2 Listed will be the Main Jet nn d and Metering Rod required to achieve the desired S fuel metering for the Primaries po s A 200 T 2 stages Lean 8
13. 3 by the pressure drop that occurs when the incoming air flow must increase in velocity in order to pass the reduced throat areas at the Main Venturi 1 and the Boost Venturi 2 This pressure drop or suction is communicated to the system by the Nozzle 3 a brass tube that opens into the inside of the Booster Venturi 2 The fuel must pass through the restriction at the Main Jet 4 and Metering Rod 5 The Rod extends through the Jet reducing the amount of area available for fuel flow If the diameter of the Rod is large then fuel flow through the Jet is more restricted than if the Rod were small After the Rod and Jet the fuel enters the Primary Well and is drawn up the inside of the Primary Well Tube 6 Sometimes this tube is called an Emulsion Tube Here the fuel is mixed with air that enters the inside of the Tube through a series of small holes The air is supplied by the Main Well Bleed 7 at the top of the Main Well The air fuel mixture exits from the top of the Main Well into a passage that leads it to discharge into the Booster Venturi 2 at the Nozzle 3 The fuel flow rate in the Main System is proportional to the air flow rate as air flow increases throttle opening the fuel flow also increases by nearly the same degree 2 Boost Venturi 1 Main Venturi 6 Primary Well Tube 7 Main Well Bleed Tr 9 Step Up Piston 10 Step Up Piston Spring 3 Nozzle PRIMARY
14. Primaries Step 3 Gi Stock Calibration Numbers in black are the steps obtainable using Calibration Kit 1486 plus the stock jets and metering rods Numbers in white are the steps obtainable using jet and rod combinations shown on this page Secondary Metering The factory calibration jet is shown in the center column For leaner or richer calibration use the jet indicated in the appropriate column 3 Stages Lean 12 2 Stages Lean 8 1 Stage Lean 4 SECONDARY Stock Calibration 1 Stage Rich 4 2 Stages Rich 8 3 Stages Rich 12 Main Jet D All Edelbrock jets have 120 prefix The JET 1423 086 JET 1424 089 JET 1425 092 JET 1426 095 JET 1427 098 JET 1429 101 JET 1430 104 last three digits minus 300 actual jet size Examples 120 386 086 jet Edelbrock p n 1423 120 401 101 jet Edelbrock p n 1429 Cruise Mode High Vacuum Low Power Rod Down 3 stages Rich 12 2 stages Rich 8 1 stage Rich 4 Base Power Mode 1 stage Lean 4 2 stages Lean 8 3 stages Lean 12 1423 086 1423 086 Power Mode Low Vacuum High Power Rod Up 3 stages Lean 12 2 stages Lean 8 1 stage Base Power Lean 4 Mode 1 stage Rich 4 2 stages Rich 896 3 stages Rich 12 Lean e Power Mode J Rich Model 1403 amp 1404 ROD JET REFERENCE CHART MAIN JET METERING RO
15. Screw Port 8 and Transfer Slot 7 Fuel in the bowl passes through the Primary Main Jet and Metering Rod Restriction 1 and into the Primary Well 2 The fuel for the Idle System is drawn through the restriction at the end of the Idle Jet 3 a brass tube and flows up the tube to the location of the 1st Idle Air Bleed 4 a brass restrictor where air is mixed with the liquid fuel The emulsified air and fuel is then drawn through the Idle Channel Restrictor 5 a drilled passage that serves to increase the velocity of the air and fuel to promote better mixing As the emulsified fuel is discharged from the Idle Channel Restrictor additional air is added at the 2nd Idle Air Bleed 6 a drilled hole and the highly aerated mixture then moves through the passages in the main body to the location of the Transfer Slot 7 and Idle Screw Port 8 The Transfer Slot 7 is a large air bleed when the throttle is closed but as the throttle is opened the slot is exposed to manifold vacuum and becomes a discharge port for Idle System fuel The Idle Screw Port is a variable discharge restriction that is adjusted by the engine tuner to achieve the desired A F Ratio at engine idle Primary Main System The Primary Main system delivers an increasing percentage of the fuel as throttle position increases phasing over the Idle System and varies fuel delivery in response to air flow and manifold vacuum Fuel is drawn through the Main System Figure
16. is felt The dimension C should be 100 between the top edge of the choke valve and the air horn To adjust bend rod B To adjust the fast idle linkage Figure 11 place the fast idle screw A between the two notches on the cam Close the choke valve as far as possible without forcing it The dimension C should be 3 64 between the choke valve and the air horn To adjust bend rod D Fast idle may be adjusted to manufacturers specifications usually 1500 rpm during normal choke cold operation The fast idle screw A can be adjusted with engine off and throttle held open to allow screw head access Recheck fast idle speed after each adjustment Bend Here FLOAT LEVEL 7 16 FIGURE 8 FLOAT DROP 15 16 TO 1 FIGURE 9 A 026 Wire Slot Piston Cylinder CHOKE PISTON LINKAGE FAST IDLE LINKAGE 8 FIGURE 10 FIGURE 11 The length of time during which the choke will stay closed is determined by the position of the choke cap As the choke cap is turned clockwise the choke will stay closed longer To properly set the choke loosen the chock housing retaining screws then turn the choke cap to the leanest notch on the choke housing and run the engine until normal operating temperature is reached With the engine running slowly turn the choke cap clockwise until the choke valve begins to close Now turn the choke housing one notch counterclockwise lean and tighten the choke housing retaining screws Periodic readjustment of the choke will be
17. 1439 060 x 052 Rod amp Jet 1426 095 1438 058 x 052 1427 098 1441 062 x 052 1427 098 1443 063 x 047 1429 101 1462 067 x 049 1430 104 1452 070 x 052 1411 Calibration Reference Chart Primary Metering Step 1 Select the combination of Cruise Mode and Power Mode Low Vacuum High Power Rod Up Power Mode fuel metering stages desired for 3 stages 2 stages 1 stage Base Power 1 stage 2 stages 3 stages i i i i Lean 12 Lean 8 Lean 4 Mode Rich 4 Rich 8 Rich 12 your calibration Normal calibration changes will be within the shaded diagonal area That is Cruise and Power mode changes should be in the same direction either richer or leaner and mt 6 OB Rich 12 usually by the same amount 2 stages Step 2 Find the number that is nearest your desired Rich 8 EON d combination This is your Calibration T 13 Reference Number Rich 4 Base Power nn o A Mode 1 stage Lean 4 2 stages 15 Lean 8 3 stages Lean Power Mode gt Rich Step 3 Find the Calibration Reference Number you have just selected in Step 2 Listed will be the Main Jet and Metering Rod required to achieve the desired fuel metering for the Primaries GC Stock Calibration Numbers in black are the steps obtainable Lean Cruise Mode Rich Cruise Mode High Vacuum Low Power Rod Down using Calibration Kit 1489 plus the s
18. 1464 CALIBRATING THE PUMP If you encounter any hesitations or stumbles that do not seem to be related to the basic metering or have not responded to changes in the basic metering move the pump drive link to one of the holes closer to the carburetor body This will increase the stroke length of the plunger and result in more pump delivery FLOAT ADJUSTMENT To properly adjust the floats in the EPS carburetor two procedures must be followed First invert the airhorn cover Figure 8 holding the airhorn gasket in place There should be 7 16 between the airhorn gasket and the top of the outer end of the float To adjust the float level bend the float lever until the recommended level is attained DO NOT press the needle into the seat when adjusting the float lever Next you should check the float drop Figure 9 Hold the airhorn upright and let the floats hang down There should be 15 16 to 1 between the airhorn gasket and the top of the outer end of the float To adjust the float drop bend the tab on the back until the recommended float drop is attained For the off road float adjustment see page 9 CHOKE ADJUSTMENT To adjust the choke piston linkage Figure 10 open the choke valve and insert a 026 wire with a 90 degree bend 1 8 from the end between the top of the slot in the choke piston cylinder and the bottom of the slot in the piston Hold the wire in position and close the choke valve by pressing on piston lever A until resistance
19. 5 065 x 047 2 Stages Rich 8 JET 1433 113 1434 116 1418 070 x 057 3 Stages Rich 12 JET 1434 116 1433 113 1461 065 x 057 1433 113 1442 063 x 037 1433 113 1443 063 x 047 Main Jet D All Edelbrock jets have 120 prefix The 1434 116 1436 068 x 057 last three digits minus 300 actual jet size 1434 116 1462 067 x 049 Examples 120 398 098 jet Edelbrock p n 1427 1434 1167 1416 065 x 042 Jet and Rod 1434 116 1461 065 057 Jet and Rod 120 413 113 jet Edelbrock p n 1433 1433 113 1449 070 x 037 1433 113 1450 070 x 042 1433 113 1451 070 x 047 1433 113 1452 070 x 052 1433 113 1418 070 x 057 1432 110 1462 067 x 049 1431 107 1442 063 x 037 1433 113 1456 073 x 047 1433 113 1455 073 x 042 1433 113 1454 073 x 037 1825 1826 Calibration Reference Chart Primary Metering Power Mode Low Vacuum High Power Rod Up 3 stages 2 stages 1 stage Base Power 1 stage 2 stages 3 stages Lean 12 Lean 8 Lean 4 Mode Rich 4 Rich 8 12 3 stages Rich 12 2 stages Rich 8 1 stage Rich 4 Base Power Mode 1 stage Lean 4 2 stages Lean 8 3 stages Lean 12 Lean Cruise Mode gt Rich Cruise Mode High Vacuum Low Power Rod Down Lean 4 Power Mode gt Rich
20. D 1460 065 x 052 1445 065 x 047 1444 065 x 037 1461 065 x 057 1441 062 x 052 1463 067 x 055 1448 068 x 052 1447 068 x 047 1446 068 x 042 1463 067 x 055 1460 065 x 052 1462 067 x 049 1452 070 x 052 1451 070 x 047 CHANGE FROM BASE 1450 070 x 042 1438 058 x 052 1437 057 x 049 1441 062 x 052 1443 063 x 047 1442 063 x 037 1445 065 x 047 1460 065 x 052 1439 060 x 052 1440 060 x 057 1436 055 x 055 1441 062 x 052 Rod amp Jet Rod amp Jet Rod amp Jet Rod amp Jet Rod amp Jet 1443 063 x 047 1403 1404 Calibration Reference Chart Primary Metering Lean lt Cruise Mode gt Rich Cruise Mode High Vacuum Low Power Rod Down 1405 Calibration Reference Chart Primary Metering Power Mode Low Vacuum High Power Rod Up 3 stages Lean 12 3 stages Rich 12 2 stages Rich 8 1 stage Rich 4 Base Power Mode 1 stage Lean 4 2 stages Lean 8 3 stages Lean 12 2 stages Lean 8 Base Power Mode 1 stage Lean 4 1 stage Rich 4 2 stages Rich 8 3 stages Rich 12 Lean lt Cruise Mode Rich Lean lt Power Mode gt Rich MAIN JET 1428 100 1428 100 1428 100 1430 104 1427
21. Hg on a vacuum gauge are metered by the Power Mode Avoid calibrating this portion of the engine s operating range too lean as spark knock detonation and piston valve burning can occur If this mode has any lean driveability symptoms surge or flat spots it is too lean and should be recalibrated at least 1 stage richer CALIBRATING THE POWER MODE STAGING The Step Up function which moves the Metering Rod to the Power Mode is controlled by the Step Up Spring The base calibration has a spring which stages rich at 5 Hg If your vehicle has a mid throttle driveability problem that is encountered as the throttle is gradually opened but then goes away upon further opening it may be possible to eliminate the lean spot by using a stronger Step Up Spring The available Step Up Springs are listed in the following chart along with their respective staging point It is best to select a new spring on the basis of vacuum readings but in the absence of a gauge try the strongest spring highest vacuum rating to see if the problem goes away If the drive problem is cured by the strong spring try the next weakest spring as well If the strong one does not help then the calibration problem is related to the A F metering stage of either the Cruise or Power Modes Use the Calibration Reference Chart to help select another combination Staging Vacuum 3 5 7 Hg A COMPLETE SET OF THESE SPRINGS IS AVAILABLE SEPARATELY AS EDELBROCK PART
22. MAIN SYSTEM FIGURE 3 from either an increase in throttle opening or an increase in engine speed at the same At higher engine loads such as in a heavy part throttle acceleration there is a need for a richer mixture This enrichment is provided by the Metering Rod and Step Up Function Figure 4 A vacuum passage 8 communicates the manifold vacuum to the underside of the Step Up Piston 9 This vacuum tries to hold the Piston in the bottom of its bore by working against the force of the Step Up Spring 10 When the manifold vacuum is high indicating a low load such as idle cruise or light acceleration it is able to overcome the force of the Step Up Spring and hold the Step Up Piston at the bottom of its bore which also positions the Metering Rod at the bottom of its travel At this point the Rod has a large diameter that creates a high restriction through the Jet and the fairly lean A F Ratio that is desirable for low load low power operation This portion of the Metering Rod is referred to as the Lean Step of the Rod ROD DOWN Lean A F Ratio HIGH LOAD Low Vacuum When the manifold vacuum is low indicating a high load such as _ Step Up Piston Step Up Spring ag 4 Metering Rod LEAN STEP In Jet LOW LOAD High Vacuum RICH STEP In Jet ROD UP a heavy part throttle or WOT acceleration the Step Up Spring is able to force the Piston to the top of its bore and position
23. Model 1825 amp 1826 ROD JET REFERENCE CHART MAIN JET METERING ROD 1426 095 1445 065 x 047 1426 095 1416 065 x 042 1426 095 1444 065 x 037 CHANGE FROM BASE 1426 095 1460 065 x 052 1426 095 1442 063 x 037 1427 098 1447 068 x 047 1426 095 1443 063 x 047 1436 068 x 057 1463 067 x 055 1441 062 x 052 1445 065 x 047 1418 070 x 057 1439 060 x 052 1453 071 x 047 1425 092 1442 063 x 037 1426 095 1462 067 x 049 1425 092 1443 063 x 047 1427 098 1427 098 1426 095 1427 098 1429 101 1426 095 1427 098 1426 095 1446 068 x 042 1426 095 1447 068 x 047 1426 095 1448 068 x 052 Step 1 Select the combination of Cruise Mode and Power Mode fuel metering stages desired for your calibration Normal calibration changes will be within the shaded diagonal area That is Cruise and Power mode changes should be in the same direction either richer or leaner and usually by the same amount Step 2 Find the number that is nearest your desired combination This is your Calibration Reference Number Step 3 Find the Calibration Reference Number you have just selected in Step 2 Listed will be the Main Jet and Metering Rod required to achieve the desired fuel metering for the Primaries Stock Calibration Num
24. anifold vacuum without a vacuum gauge some of the calibration procedures will be more difficult Changing Components Metering Rod and Step Up Spring changes can typically be made in less than five minutes and without removing the carburetor First loosen the Step Up Piston Cover Screws See pg 32 and twist the Step Up Piston Cover Plates to the side The Metering Rods and Step Up Springs can now be removed and replaced if necessary Be sure to replace the Step Up Piston Cover Plate and tighten the Step Up Piston Cover Screw when finished CAUTION Do not overtighten the Step Up Piston Cover Screws They should only be tightened to 12 to 17 inch pounds Excessive torque will weaken or snap off the screw heads If this happens they may fall into the carb causing serious engine damage If an inch pound torque wrench is not available snug the screw until it just touches the plate then tighten 1 16th turn more To replace the Primary or Secondary Metering Jets first remove the Metering Rods and Step Up Springs as outlined in the preceding paragraph Next disconnect the Choke Cam Connector Rod Pump Connector Rod and Choke Connector Rod when applicable Finally remove the 8 Airhorn Attaching Screws and remove the Airhorn from the carburetor body A standard screwdriver can now be used to remove the appropriate Metering Jets Once desired Metering Jets have been installed the carb may be reassembled by reversing this procedure IDLE MIXTURE T
25. bers in black are the steps obtainable using Calibration Kit 1842 plus the stock jets and metering rods Numbers in white are the steps obtainable using jet and rod combinations shown on this page Secondary Metering The factory calibration jet is shown in the center column For leaner or richer calibration use the jet indicated in the appropriate column 3 Stages Lean 12 2 Stages Lean 8 1 Stage Lean 4 SECONDARY Stock Calibration JET 1427 098 1 Stage Rich 4 JET 1429 101 JET 1424 089 JET 1425 092 JET 1426 095 2 Stages Rich 8 JET 1430 104 3 Stages Rich 12 JET 1431 107 Main Jet D All Edelbrock jets have 120 prefix The last three digits minus 300 actual jet size Examples 120 398 098 jet Edelbrock p n 1427 120 413 113 jet Edelbrock p n 1433 ITEM DESCRIPTION Step up piston cover screws 2 Step up piston cover plates 2 Step up pistons 2 Step up metering rods 2 Step up piston springs 2 Step up rod retainer springs 2 Pin springs small 3 Choke connector rod amp lever Choke piston housing 9a Choke piston housing seal Exploded View of Edelbrock Performer Series Carburetor 9b Choke filter 10 Mounting screws 3 10a Choke housing retainers 3 11 Thermostatic coil assembly 2 Baffle plate 3 Choke housing gasket 4 Choke cam connector rod 5 Pump connector rod 6 Airhorn at
26. ch Model 1805 amp 1806 ROD JET REFERENCE CHART MAIN JET METERING ROD CHANGE FROM BASE 1426 095 1447 068 x 047 1426 095 1446 068 x 042 1426 095 1448 068 x 052 1425 092 1443 063 x 047 1427 098 1453 071 x 047 1426 095 1462 067 x 049 1426 095 1444 065 x 037 1426 095 1416 065 x 042 1426 095 1445 065 x 047 1426 095 1460 065 x 052 1427 098 1447 1427 098 068 x 052 068 x 047 Jet and Rod 1425 092 1416 065 x 042 1425 092 1445 065 x 047 1426 095 1450 070 x 042 070 x 047 1424 089 1442 063 x 037 Lean ge Cruise Mode gt Rich Step 1 Select the combination of Cruise Mode and Power Mode fuel metering stages desired for your calibration Normal calibration changes will be within the shaded diagonal area That is Cruise and Power mode changes should be in the same direction either richer or leaner and usually by the same amount Step 2 Find the number that is nearest your desired combination This is your Calibration Reference Number Step 3 Find the Calibration Reference Number you have just selected in Step 2 Listed will be the Main Jet and Metering Rod required to achieve the desired fuel mete
27. communicated into the system by the Secondary Nozzle 4 Fuel flows through the Secondary Main Jet 5 to the Secondary Well where it is drawn through the Secondary Well Tube 6 The fuel is mixed with air that enters the tube through a series of small holes The source of the air is one of the Secondary Well Bleeds 7 There are two air bleeds one admits air to the outside of the Well Tube and the other allows air to flow into the passage behind the Nozzle The fuel now well mixed with air flows through the slightly up hill passage and exits into the Secondary Boost Venturi 3 through the Secondary Nozzle 4 3 Secondary Boost Venturi 4 Secondary Nozzle 7 Secondary SECONDARY MAIN SYSTEMS Well Bleeds FIGURE 5 2 bleeds 6 Secondary Well Tube 5 Secondary Main Jet y 1 Secondary 33 Throttle TRANSIENT CONTROL SYSTEMS In addition to the three 3 basic Metering Systems there are two 2 Transient Control Systems The Secondary Auxiliary System and The Pump System Secondary Auxiliary System During the initial stages of Secondary Operation the air flow rate through the secondaries is very low Accordingly there is not enough pressure drop suction at the Secondary Nozzle to induce fuel flow In order to prevent a lean A F condition that would be experienced by the driver as a bog or flat spot on secondary opening it is necessary to add fuel by an auxiliary means during the
28. dary Main System EEN 4 TRANSIENT CONTROL SYSTEMS eese trenes 4 1 Secondary Auxiliary System 4 2 PUMP SYSTEM i ce cec itm ni rte ere a te impen e als 5 EXTERNAL SU 5 Fuel Pumps and Pressure EEN 5 KEEN 5 SECTION 2 TUNING PROCEDURE ai 5 REVISING THE CALIBRATION 5 Parts and Equipment sse rnnt nennen 6 Changing Lompopernts ENEE 6 IDLE MIXTURES ete ashi near nike 6 Winter Fuel Idle Sets cccsssescsssssssessesssessessssssssssseseseesecsessescassaessssessceasessesassossaseaess 6 Long Duration Camshaft 7 CALIBRATING THE WIDE OPEN THROTTLE WOT sn 7 CALIBRATING THE PART THROTTLE esent 7 Ur iSe s eter teet ete 7 Power Mode a tci erahnen 7 CALIBRATING THE POWER MODE STAGING ener 8 CALIBRATING THE POMP sese nnne 8 FLOAT ADJUSTMENT ea aa 8 CHOKE ADJUSTMENT esee aiana 8 SPECIAL GALIBRATIONS essent nnne 9 CARBURETOR SPECIFICATIONS eerie trennen rnnt 9 CALIBRATION REFERENCE CHARTS ee 10 19 APPENDIX ett ei cien atit rete eee tete lan and 20 23 Exploded VIEW al 20 21 Troubleshooting Information
29. elect the combination of Cruise Mode and Power Mode fuel metering stages desired for Power Mode Low Vacuum High Power Rod Up your calibration Normal calibration changes 3 stages 2 stages 1 stage Base Power 1 stage 2 stages 3 stages will be within the shaded diagonal area That is Lean 12 Lean 8 Lean 4 Mode Rich 4 Rich 8 Rich 12 Cruise and Power mode changes should be in the same direction either richer or leaner and usually by the same amount 3 stages ot AN Rich 1296 Step 2 Find the number that is nearest your desired combination This is your Calibration Reference Number 2 stages Rich 8 1 stage SZT Ke Base Power 3 Mode 6 1 stage gor e TT Lean 4 2 stages 5 L I 020 pam ol S 3 stages Lean 12 2 using Calibration Kit 1487 plus the stock jets and metering rods Numbers in white are the steps obtainable using jet Lean 4 amp Power Mode gt Rich and rod combinations shown on this page Step 3 Find the Calibration Reference Number you have just selected in Step 2 Listed will be the Main Jet and Metering Rod required to achieve the desired fuel metering for the Primaries Stock Calibration Numbers in black are the steps obtainable Lean gn Cruise Mode gt Rich Cruise Mode High Vacuum Low Power Rod Down Model 1406 ROD JET REFERENCE CHART Secondary Metering The factory calibration jet is shown in the cente
30. f original purchase by such consumer Any implied warranty determined to be applicable is limited in duration to the duration of this warranty Some states do not allow limitations on how long an implied warranty is so the above limitation may not apply to you In the event of a defect in material or workmanship Edelbrocks sole responsibility is to repair or replace the defective product This warranty covers the replacement or repair at Edelbrock s option of the product only and does not cover the cost of removal or installation of the product Final warranty determination will be the decision of EDELBROCK EDELBROCK does not warrant products which have been modified or altered outside factory specifications subjected to conditions such as misuse neglect accident improper installation or adjustment dirt or other contaminants weather or corrosion gum or varnish use of improper or poor quality fuel or fuel additives improper fuel pressure and faulty repair or use in other than those automotive applications recommended in a current EDELBROCK catalog Further there are no warranties which extend beyond those stated here EDELBROCK shall not be responsible for a actual or alleged labor transportation or other incidental charges b actual or alleged consequential or other damages incurred by use of EDELBROCK Performer Series Carburetors Edelbrock Corp shall not be liable for any and all consequential damages occasioned by the breach of any writte
31. he Edelbrock Performer Series carburetor has conventional Idle Mixture Screws IMS that provide a leaner A F when turned clockwise and richer A F when turned counter clockwise The idle air flow is controlled by a conventional screw that opens the Primary Throttles The following procedure should be used to set the idle mixture and speeds 1 Fully warm engine and ensure choke is fully open 7 Reset the speed 2 Air cleaner in place 8 Carefully trim each IMS to again get the maximum idle RPM 3 Set desired speed with the air screw 9 Go leaner just enough to get a 20 RPM drop in speed 4 Adjust the IMS on ONE side to get the maximum possible RPM 10 Reset the speed to the desired RPM Do not go rich beyond the maximum speed point 11 This is a Lean Best Idle Set Setting richer than this will not 5 Ifthe above changed the idle speed more than 40 RPM then readjust the speed improve idle quality or performance but could tend to foul plugs 6 Adjust the side OPPOSITE of that in Step 4 to get maximum RPM Winter Fuel Idle Sets During the winter months in most parts of the country the local fuel will be a winter blend that is very volatile as an assist to cold engine starting and driveability during warm up However the high volatility has the disadvantage of allowing excessive vaporization of the fuel if the vehicle is operated in a heated area such as a garage This can result in problems in the idle set procedures since the carbu
32. hol with gasoline Methanol blended fuel should not be used in your Edelbrock Performer Series carburetor as it will cause corrosion of the fuel system components It can also cause rapid failure of seals gaskets diaphragms and pump plungers Always check to see if you are using a blended fuel Although the pump may not indicate the fuel is blended it is always advisable to verify the type of fuel the station carries Blown Engines Two model 1405 carburetors should be used on engines with positive displacement superchargers such as GMC 6 71 blowers or equivalent The following calibration changes make an excellent starting point Primary Jets 101 1429 Secondary Jets 101 1429 Metering Rods 070 x 042 1450 Step up Piston Springs 5 orange stock Needle amp Seat assemblies 110 1466 This calibration has been tested on engines ranging in size from 350 c i d Chevys to 440 c i d Chryslers with good results CARBURETOR SPECIFICATIONS ALL MODELS Main Main Metering Float Pump Accelerator Venturi Venturi Throttle Throttle Jet Jet Rod Drop Drive Pump Diameter Diameter Bore Bore Primary Secondary Primary z1 4 Link Nozzle Primaries Secondaries Diameter Diameter only Location Diameter Primaries Secondary 065 x 052 orange 5 0935 7 16 middle hole 1 3 16 1 9 16 1 7A6 1 11 16 065 052 orange 5 0935 7 16 middle hole 1 3 16 1 9 16 1 7 16 1 11 16
33. into the throat of the FIGURE 7 carburetor Figure 7 The Edelbrock carburetor has a piston that draws fuel into the pump cavity past the plunger lip seal when the throttle is closing 1 Upon opening the lip seal seats allowing the plunger to force the fuel through another one way valve the Pump Discharge Ball and Weight 2 and the Pump Jets 3 into the primary throats amp 2 P 2 Pump Discharge Ball amp Weight Tut 4 Pump Drive Spring D The pump plunger is not driven directly by the throttle but through an 1 Inlet intermediate Pump Drive Spring 4 that extends the duration of the pump f ie e shot past the time the throttle stops moving The Edelbrock Performer NT Aem Series carburetor has an external pump lever with three hole locations for link attachment providing three distinct pump delivery curves This is further explained in Calibrating The Pump RUN EXTERNAL DEVICES The function of your Edelbrock Performer Series carburetor is also dependent on several external devices the fuel pump and air cleaner Fuel Pumps and Pressure Avoid extremes in fuel pressure At IDLE there should not be any more than 6 0 psi if the vehicle has an adjustable fuel pressure regulator set it to 5 5 psi With most fuel pumps the minimum fuel pressure is encountered at high rpm and WOT Fuel pressure should not drop below 2 0 psi If it does a fuel pump with more capacity may be required
34. irt metal shavings between the needle and seat or a sticking float To correct either of these problems lightly tap the carburetor fuel inlet area with the handle of a screwdriver If flooding continues pinch the fuel line if possible Start the engine and let it run until it stops Release line and restart engine If flooding persists examine the needles seats float level and float drop Adjust or replace parts if necessary Excessive under hood temperature Ensure fuel line is not located too close to heat sources such as the exhaust or block causing expanding fuel to be forced past the needle and seat Fuel can also boil inside the carburetor due to missing gaskets spacers or heat shields Also check to see if the exhaust heat riser is stuck allowing excessive heat under the carburetor Use Edelbrock Divided Heat Insulator Gasket 9266 for dual plane manifolds Square Bore Heat Insulator Gasket 9265 for single plane manifolds and 9267 Heat Insulator Gaskets for dual quad manifolds Excessive fuel pump pressure See page 5 Warranty EDELBROCK warrants its Performer Series Carburetors to be free from defects in material or workmanship This warranty is valid provided that the product is properly installed subjected to normal use and service and is not modified or changed in any way or used for racing or competition purposes This warranty is extended to the original consumer purchaser and has a duration of 90 days from date o
35. is shown in the center column i i ii For leaner or richer calibration use the jet indicated in the e pe Ge appropriate column 098 068 042 1429 101 1456 073 x 047 3 Stages Lean 12 JET 41425 092 1421 098 1450 070 042 1427 098 1451 070 x 047 2 Stages Lean 8 JET 1426 095 1427 098 bag 1452 070 X 052 1 Stage Lean 4 JET 1427 098 1426 095 1443 063 x 047 Rod amp Jet SECONDARY Stock Calibration JET 1429 101 1426 0957 1460 065 052 Rod amp Jet ne 1425 092 1443 063 x 047 Rod amp Jet 1 Stage Rich 4 JET 1430 104 1426 095 1452 070 x 052 2 Stages Rich 8 JET 1431 107 1426 095 1447 068 x 047 3 Stages Rich 12 JET 1432 110 1425 092 1444 065 x 037 1427 098 1456 073 x 047 1429 101 1459 075 x 047 Main Jet D All Edelbrock jets have 120 prefix The 1427 098 1454 073 x 037 last three digits minus 300 actual jet size 1429 101 1458 075 x 037 Examples 120 398 098 jet Edelbrock p n 1427 1430 104 1459 075 x 047 Rod amp Jet at ven EE 1430 104 1456 073 x 047 Rod amp Jet STS Jet Edelbrock pni 1433 1427 098 1444 065 x 037 1429 101 1451 070 x 047 1427 098 1445 065 x 047 1427 098 1460 065 x 052 1426 095 1441 062 x 052 Rod amp Jet 1426 095
36. ition As explained in the Theory of Operation the Step Up function modulates the Rods between the Cruise and Power positions The part throttle calibration is more individualized than is the Wide Open Throttle WOT It is not measured by absolute numbers but reflects the driver s feel for a particular combination Carefully evaluate the driveability with the carburetor at the calibration level determined from the WOT exercise Drive at a variety of engine speeds and throttle openings looking for any flat spots or lean surge conditions Cruise Mode If there are any surge or flat spot conditions in the steady speed cruises or light accelerations a lean condition probably exists Consult the Calibration Reference Chart and change to 1 stage rich in the Cruise Mode If it gets better but not completely fixed keep going in the rich direction The Calibration Reference Chart will give you Rod and Jet combinations that are directionally correct or you may choose your own If the light throttle is satisfactory trying going 1 stage lean in the Cruise Mode If there are still no problems with surge or other indications of lean metering do not hesitate to go to 2 stages lean in the Cruise Mode A lean Cruise Mode has advantages in fuel economy and keeping the plugs clean Keep going until you begin to notice driveability problems and then back up 1 stage Power Mode Accelerations at part throttle with low manifold vacuum less than about 5
37. lean See Tuning Procedure Check float level and drop See page 8 Check idle mixture screw adjustment See page 6 Too rich See Tuning Procedure Increase accelerator pump stroke Pump squirter size change may be needed See page 8 Off road vehicle may need spring loaded needle and seat kit pg 9 Check for dirt or metal in needles and seats Needles and seats may need replacement See page 23 Check for dirt blocking the low speed circuit Clean unit and apply air pressure Install in line fuel filter 8873 Check floats for leakage Replace if necessary Check air horn gasket Replace if deterioration or breakage is present Fuel is boiling due to excessive under hood temperature See page 23 Fuel pressure too high Fuel regulator may be needed See page 5 Fuel pressure too low Check fuel system See page 5 Check secondary latching device and rod for proper movement Lower float level from 11 32 to 7 16 See page 8 SYMPTOMS 8 5 en 5 x eo Soe Re ka c e 5 e o gt 5 EC cC B _ o 5 ott o a E I c o Ct eom Gm Ke a S9 5 9 B Q E T S 853 wer x ka E 5 ses co oc o sS o cC e 72 o 5 3 5 c 2 c 22 eo 2353 2 ceo x c 9 Ze ses 8 Z2 B S 9 8852853 f os c ca ca x SJ ES eo e 5 Stumbles or loads up N Troubleshooting Information D
38. lections This is your calibration reference number Locate your calibration reference number to determine the rod jet combination for your application For example you have a 1405 Edelbrock Performer Series carburetor You have determined by reading the rest of the manual you would like to go 1 stage lean in the Cruise Mode and 2 stages lean in the Power Mode The intersection of these two lines lies on the number 21 This is your calibration reference number Now look below the Calibration Table to the Rod Jet Reference Chart Find the number 21 under the REF column The jets you should use are 098 and the rods are 070 x 052 Located at the very bottom of each Calibration Reference Chart is a guide for changing your Secondary Metering This will be useful when calibrating the wide open throttle WOT Before you attempt to establish a new calibration be sure that the engine is in a sound state of tune All ignition items must be in proper working order including reasonably fresh plugs of the correct heat range Timing should be properly set and the air filter element and fuel filter should be clean Proper fuel pressure should be verified and cracked or brittle vacuum lines should be eliminated Many so called carburetor calibration problems have been traced to another part of the engine system that was not functioning properly CAUTION Be alert to carburetor flooding when fuel is first applied Flooding can be caused by dirt small partic
39. les of hose cuttings floats and inlet needles which have settled during shipping or by other conditions as discussed below Each Edelbrock Performer Series carburetor is flow tested in the factory for both air and liquid flow so flooding is rare However for safety sake please observe this caution When the fuel pump is turned on or when the engine is first started watch closely for signs of flooding If flooding is apparent tap the body of the carburetor lightly with a rawhide mallet or the wooden handle of a small hammer If flooding continues pinch the fuel line hose to shut off flow run the engine to clear the carburetor and let the fuel line flow again If flooding continues pinch the fuel line hose to shut off flow run the engine to clear the carburetor and let the fuel line flow again If flooding still continues stop the engine Clean up any raw gasoline and refer to the Trouble Shooting section of the Owner s Manual Parts and Equipment Aside from ordinary hand tools the following items are recommended Edelbrock Performer Series Carburetor Jet Set Contains selections of Main Jets Metering Rods and Springs Tachometer If the vehicle is not equipped with a tach the dwell meter style tach will be adequate If neither is available you will be able to use the speedometer in place of the tach for some of the procedures but it will not be as convenient Vacuum Gauge Should be hooked up to read engine s intake m
40. low across the top of the carburetor s such as on an open bodied car or full bodied vehicle with a tunnel ram manifold The flow of air across the carburetor will result in an upset to the fuel metering that cannot be accommodated by recalibration since the change to the A F Ratio will be different for every vehicle speed SECTION 2 TUNING PROCEDURE Before proceeding please ensure you have installed your Edelbrock Performer Series Carburetor according to the Carburetor Installation Instructions included with the carburetor REVISING THE CALIBRATION The Edelbrock Performer Series Carburetor is designed to allow quick and easy changes to the metering Virtually any change imaginable can be performed without removing the carburetor from the manifold and the most common changes may be performed in less than five minutes without removal of the airhorn bowl cover To help you calibrate your carburetor a CALIBRATION REFERENCE CHART has been designed for each model of the Edelbrock Performer Series carburetor These charts pages 10 19 each consist of two sections A Calibration Table and a Rod Jet Reference Chart After reading the Calibration procedures the next step in calibrating your carburetor is to look at the Calibration Table for your model carburetor Determine if you would like to go richer or leaner in the Cruise Mode and do the same for the Power Mode Select the number that is closest to intersection of your Cruise and Power Mode se
41. n or implied warranty pertaining to this sale in excess of the purchase price of the product Warranty claims will be initiated by returning the alleged defective product to the place of purchase with dated purchase receipt and with completed applicable EDELBROCK warranty claim tag Do not send the product directly to EDELBROCK Edelbrock Carburetor Data Log p This warranty gives you specific legal rights and you may also In order to get the most from your Edelbrock carburetor purchase please complete and mail the enclosed have other rights which vary from state to state warranty card Also you may want to record your calibration settings in the table below and keep it with your vehicle records The general limited Warranty supersedes all prior warranty statements Inquiries concerning this warranty should be Model Purchase Date directed to PUMP DRIVE NEEDLE REFERENCE PRI SEC STEP UP LINK PUMP AND CHART For further information contact the DATE JET JET SPRING LOCATION CLUSTER LOCATION Edelbrock Technical Department Between 7 00 am and 5 00 pm PST Monday through Friday Tech Line 800 416 8628 Offices 310 781 2222 FAX 310 320 1187 Notes Notes 442022 zs
42. perform your WOT calibration is on a chassis dyno If one is not available then consider a safe legal driving space such as a drag strip where you are given E T and MPH data 1 Select an RPM Range to use in evaluating the WOT power As a rule use the highest 50 percent of the real power band If your engine makes good power up to 5000 RPM then 2500 5000 is a good range If peak power is at 6500 then 3500 6500 would be a good pick Be sure not to select RPMs that are higher than the engine s useful power band 2 Accelerate at WOT from 1000 RPM below the range you have elected to a few hundred over the range Time the acceleration with a stop watch Be sure to time only the interval while the engine is sweeping through the selected range Make enough timed accelerations to get a good average that is not affected by wind or grade 3 Refer to the Calibration Reference Chart for your model Find the richest Power Mode Primary Metering change you can make without changing a Jet a Rod change only This will probably be 2 stages 8 rich 4 Change to the indicated Rods Perform timed acceleration 2 Compare the times Do not be surprised if there is no difference 5 Compare the results of timed acceleration 2 to the base calibration and refer to the following section that best describes your situation Case 1 Faster than base calibration Change Secondaries 2 stages richer and perform acceleration test 3 e If test 3 is the same as 2
43. r column For leaner or richer calibration use the jet indicated in the appropriate column MAIN JET METERING ROD CHANGE FROM BASE 1427 098 1459 075 047 stock calibration 3 Stages Lean 12 JET 1423 0867 1426 095 1449 070 x 037 Rod amp Jet 2 Stages Lean 8 JET 1424 089 1427 098 1458 075 x 037 1 Stage Lean 4 JET 1425 092 1425 092 1446 068 x 042 Rod amp Jet 1426 095 1453 071 x 047 Rod amp Jet SECONDARY Stock Calibrat JET 1426 095 ae 095 1425 092 1447 068 x 047 Rod amp Jet 1 Stage Rich 4 JET 1427 098 1426 095 1456 073 x 047 Rod amp Jet 2 Stages Rich 8 JET 1429 101 1426 095 1455 073 x 042 Rod amp Jet 3 Stages Rich 12 1430 104 1426 095 1454 073 x 037 Rod amp Jet 1425 092 1451 070 x 047 Rod amp Jet 1425 092 1453 071 x 047 Rod amp Jet Main Jet l D AII Edelbrock jets have 120 prefix The 14251045 N last three digits minus 300 actual jet size 1425 092 1449 070 x 037 Rod amp Jet A 1426 095 1458 075 x 037 Rod amp Jet Examples 120 398 098 jet Edelbrock p n 1427 1426 095 1448 068 x 052 Rod amp Jet 120 401 101 jet Edelbrock p n 1429 1426 095 1447 068 x 047 Rod amp Jet 1427 098 1453 071 x 047 1429 101 1459 075 x 047 1427 098 1449 070 x 037 1425
44. required as the temperature changes throughout the year It is recommended that you use the notches in the choke housing as a reference one notch clockwise for rich or one notch counterclockwise for lean After each adjustment verify that the choke valve opens fully after the engine is warm SPECIAL CALIBRATIONS The preceding calibrations and adjustments apply to carburetors used in general street applications In the following extreme instances special calibration procedures may need to be followed Off Road Although the Edelbrock Performer Series carburetor was not calibrated with hill climbing and other extreme off road operation in mind it can be made to perform superbly by substituting Edelbrock 1465 spring loaded needle and seat for the original needle and seat The spring loaded needle and seat act like a shock absorber reducing the possibility of flooding during off road operation After installation of the new needle and seat you must reset the float level to 7 16 and drop the float drop to 15 16 to 1 as outlined in FLOAT ADJUSTMENT High Fuel Flow When evidence of fuel starvation exists first ensure that proper pressure 4 5 psi minimum is maintained at WOT If proper fuel pressure is supplied and fuel starvation still exists it may be necessary to change the needle and seat to a larger size 1466 Do not make this change unless absolutely required as the smaller inlet is preferred for proper fuel control under most conditions
45. retor s internal vents will allow this excess vapor to be drawn into the throats and enrichen the mixture The idle will be erratic and not seem to be able to hold a set To resolve this type of problem it is advisable to perform the final settings outdoors after the vehicle has been stabilized with a drive of several miles Long Duration Camshaft If the engine has a fairly radical camshaft it may require an excessive amount of throttle opening for idle and or have low idle vacuum levels Either condition can lead to poor levels of adjustability and erratic idles Another fix for the above condition is to run as much spark advance as possible at idle If the distributor is fitted with a vacuum advance unit connect it directly to manifold vacuum If you are not able to employ vacuum advance for some reason then the mechanical curve should have a low limit which will allow you to use plenty of initial spark advance e Measure the manifold vacuum at idle If it is below 7 Hg there is a good chance that the Metering Rods are in the up rich position When combined with a high idle air rate this can cause the Nozzles to discharge fuel at idle Use a weaker Step Up Spring see section on Step Up calibration to keep the Rods down at idle With some cams a stiffer spring pink or silver is necessary Experimentation is the best way to determine which is best for your application CALIBRATING THE WIDE OPEN THROTTLE WOT The best place to
46. ring for the Primaries Stock Calibration Numbers in black are the steps obtainable using Calibration Kit 1840 plus the stock jets and metering rods Numbers in white are the steps obtainable using jet and rod combinations shown on this page Secondary Meterin The factory calibration jet is shown in the center column For leaner or richer calibration use the jet indicated in the appropriate column 3 Stages Lean 12 JET 1424 089 2 Stages Lean 8 JET 1425 092 1 Stage Lean 4 JET 1426 095 SECONDARY Stock Calibration JET 1427 098 1 Stage Rich 4 JET 1429 101 2 Stages Rich 8 JET 1430 104 3 Stages Rich 12 JET 1431 107 Main Jet D All Edelbrock jets have 120 prefix The last three digits minus 300 actual jet size Examples 120 398 098 jet Edelbrock p n 1427 120 413 113 jet Edelbrock p n 1433 1812 1813 Calibration Reference Chart Primary Metering Step 1 Select the combination of Cruise Mode and Power Mode fuel metering stages desired for Power Mode Low Vacuum High Power Rod Up your calibration Normal calibration changes 3stages 2 stages 1 stage Base Power 1 stage 2stages stages will be within the shaded diagonal area That is Lean 12 Lean 8 Lean 4 Mode Rich 4 Rich 8 Rich 12 Cruise and Power mode changes should be in the same direction either richer or leaner and usually by the same amount a Step 2 Find
47. rmal calibration changes will be within the shaded diagonal area That is Cruise and Power mode changes should be in the same direction either richer or leaner and usually by the same amount Step 1 Find the number that is nearest your desired combination This is your Calibration Reference Number Step 2 Find the Calibration Reference Number you have just selected in Step 2 Listed will be the Main Jet and Metering Rod required to achieve the desired fuel metering for the Primaries Step 3 Stock Calibration Numbers in black are the steps obtainable O using Calibration Kit 1479 plus the stock jets and metering rods Numbers in white are the steps obtainable using jet and rod combinations shown on this page Secondary Metering The factory calibration jet is shown in the center column For leaner or richer calibration use the jet indicated in the appropriate column 3 Stages Lean 12 2 Stages Lean 8 1 Stage Lean 4 SECONDARY Stock Calibration 1 Stage Rich 4 2 Stages Rich 8 3 Stages Rich 12 JET 1423 086 JET 1424 089 JET 1425 092 JET 1426 095 JET 1427 098 JET 1429 101 JET 1430 104 Main Jet D All Edelbrock jets have 120 prefix The last three digits minus 300 actual jet size Examples 120 398 098 jet Edelbrock p n 1427 120 400 100 jet Edelbrock p n 1428 1406 Calibration Reference Chart Primary Metering Step 1 S
48. run anywhere between 5 and 25 AF the 16 0 usual target values for un supercharged engine a fairly narrow A wn range Figure 1 A F is about 12 5 for the WOT and 14 0 15 5 at 15 0 xDD part throttle cruise An intermediate value of about 13 5 14 0 is F usually used for mid range power non WOT acceleration 14 0 R A T 13 0 I o 120 11 0 Rich m 1000 2000 3000 4000 5000 6000 7000 8000 9000 Engine RPM TYPICAL ENGINE A F RATIOS FIGURE 1 METERING SYSTEMS The Edelbrock carburetor has three 3 basic systems that meter fuel to the engine The Idle System Primary Main System and Secondary Main System By understanding the operation of each 4 2nd idle Air Bleed you will be better prepared to calibrate your carburetor Tru Idle Channel Restrictor 4 1st Idle Air Bleed Idle System The Idle System delivers 100 of the idle fuel It also meters fuel at off idle throttle positions a large percentage at just off of idle decreasing to a minor influence as the throttle is opened wider The idle setting is critical both to a smooth idle at proper rpm and to a smooth transition to part throttle operation 2 Primary Well 3 Idle Jet a 1 Main Jet and Metering Rod een 4 25 LZ EL UI Transfer Slot a L EH ch EX ZF 8 Idle Screw Port IDLE SYSTEM FIGURE 2 Fuel is drawn through the Idle System Figure 2 by the intake manifold vacuum that is communicated at the Idle
49. taching screw 1 7 Airhorn attaching screws 8 a u 18 19 20 21 22 23 24 25 26 Airhorn assembly Pump arm screw Pump arm Pump connector link Fuel inlet fitting Fuel Strainer Screens 2 Fuel inlet fitting gasket Float lever pins 2 Float amp lever assemblies 2 27 Needle amp seat assemblies 2 28 Airhorn gasket 29 Pump plunger assembly 30 Pump plunger spring 31 Primary cluster screws 4 32 Primary venturi boosters 2 33 Venturi booster gaskets 2 34 Pump jet housing screws 2 35 Pump jet housing Electric choke models 1406 1409 1410 amp 1411 Pump jet housing gasket Pump discharge weight Pump discharge ball Secondary booster screws 4 Secondary venturi boosters 2 Venturi booster gaskets 2 Air valve amp weights Primary metering jets 2 Secondary metering jets 2 45 46 4f 48 49 50 51 52 Fuel bowl baffle plates 2 Idle mixture screws amp springs 2 Fast idle cam Idle speed screw Body assembly Ported vacuum port Full time vacuum port PCV valve port Troubleshooting Chart POSSIBLE SOLUTION Check for air leaks Make sure carburetor and manifold gaskets seal properly All outlets must be plugged or connected Check ignition system Replace parts as necessary Adjust timing to proper specifications Check choke adjustment See page 8 Change carburetor fuel filter and or in line fuel filter Too
50. the Metering Rod at the top of its travel This action is called Power Mode Staging The portion of the rod now located in the jet has a smaller diameter thus the restriction through the Jet is reduced and a rich A F Ratio is provided for high load high power operating conditions This is the Rich Step of the Rod METERING ROD AND STEP UP FUNCTION FIGURE 4 Main Jet WA d Rich A F Ratio Secondary Main System The Secondary Main System Figure 5 delivers fuel only when the secondary throttle blades and air valve are open It ensures that fuel delivery varies with air flow The Secondary Throttles 1 begin to open when the Primaries are about 65 open The Primary and Secondary Throttles arrive at the WOT stop at the same time Air flow through the Secondary side is controlled by Air Valves 2 These valves are located in the secondary bores above the throttle blades They are balanced against a counter weight and open to admit additional air flow only if there is enough air velocity to allow the proper operation of the Secondary Metering Systems The principles of operation for the Secondary Main System are the same as those that govern the operation of the Primary Main System the pressure drop suction arises from the increase in the airs velocity as it passes through the Venturi sections The pressure drop suction at the Secondary Booster Venturi 3 is
51. the number that is nearest your desired mem n a A 2 stages combination This is your Calibration Rich 8 Reference Number Step3 Find the Calibration Reference Number you have Bier just selected in Step 2 Listed will be the Main Jet and Metering Rod required to achieve the desired Base Power s Mod fuel metering for the Primaries xd 1 stage Lean 4 2 stages Lean 896 D Stock Calibration 3 stages Lean lt Cruise Mode Rich Lean 12 Cruise Mode High Vacuum Low Power Rod Down Numbers in black are the steps obtainable using Calibration Kit 1841 plus the stock jets and metering rods Numbers in white are the steps obtainable using jet and rod combinations shown on this page Lean e Power Mode gt Rich Model 1812 amp 1813 Secondary Metering ROD JET REFERENCE CHART The factory calibration jet is shown in the center column For leaner or richer calibration use the jet indicated in the REF MAIN JET METERING ROD CHANGE FROM BASE appropriate column 1433 113 1447 068 x 047 3 Stages Lean 12 JET 1427 098 1433 1137 1446 068 x 042 1434 116 1455 073 x 042 2 Stages Lean 896 JET 1429 101 1433 113 1448 068 X 052 1 Stage Lean 4 JET 1430 104 1433 113 1436 068 x 057 SECONDARY Stock Calibration JET 1431 107 1433 1137 1444 065 x 037 1 Stage Rich 4 JET 1432 110 eu nee age Rich 4 110 1433 113 144
52. the steps obtainable using jet and rod combinations shown on this page Numbers in black are the steps obtainable Model 1412 amp 1413 Secondary Metering ROD JET REFERENCE CHART The factory calibration jet is shown in the center column For leaner or richer calibration use the jet indicated in the appropriate column MAIN JET METERING ROD CHANGE FROM BASE 1433 113 1453 071 x 047 3 Stages Lean 12 JET 1425 092 1433 113 1450 070 x 042 2 Stages Lean 8 JET 1426 095 1433 113 1449 070 x 037 1434 116 1454 073 x 037 Rod amp Jet 1 Stage Li 4 JET 1427 098 age Lean 1 098 1431 107 1443 063 x 047 Rod amp Jet SECONDARY Stock Calibration JET 1429 101 1432 110 1445 065 x 047 1 Stage Rich 4 JET 1430 104 1433 113 1452 070 x 052 2 Stages Rich 8 JET 1431 107 1432 110 1441 062 x 052 a 1433 113 1447 068 x 047 3 Stages Rich 12 JET 1432 110 1434 116 1456 073 x 047 Rod amp Jet 1432 110 1443 063 x 047 Rod amp Jet Main Jet D All Edelbrock jets have 120 prefix Th an EE ain Jet 1 D All Edelbrock jets have 120 prefix The u u u last three digits minus 300 actual jet size 1434 C116 1403 071X Examples 120 398 098 jet Edelbrock p n 1427 1433 113 1443 063 x 047 120 413 113 jet Edelbrock p n 1433 1433 113 1442
53. tock jets and metering rods Numbers in white are the steps obtainable using jet and rod combinations shown on this page 1453 071 x 047 Model 1411 ROD JET REFERENCE CHART Secondary Meterin METERING ROD HANGE FROM BASE GRO CHANGE FROM BAS The factory calibration jet is shown in the center column 1459 075 x 047 ibrati For leaner or richer calibration use the jet indicated in the 1419 075 x 042 appropriate column 1458 075 x 037 1454 073 x 037 Rod amp Jet 3 Stages Lean 12 JET 1427 098 1456 073 x 047 Rod amp Jet 2 Stages Lean 8 JET 1429 101 1457 073 x 052 BO Rue 1 Stage Lean 4 JET 1430 104 1445 065 x 047 Rod amp Jet g HN 104 1416 065 x 042 Rod amp Jet SECONDARY Stock Calibration JET 1431 107 1444 065 x 037 Rod amp Jet 1 Stage Rich 4 JET 1432 110 1456 073 x 047 2 Stages Rich 8 JET 1433 113 1455 073 x 042 1447 068 x 047 1448 068 x 052 Rod amp Jet 1458 075 x 037 Rod amp Jet Main Jet D All Edelbrock jets have 120 prefix The 1449 070 x 037 last three digits minus 300 actual jet size 1450 070 x 042 Examples 120 398 098 jet Edelbrock p n 1427 070 x 047 120 413 113 jet Edelbrock p n 1433 1432 110 1418 070 x 057 1432 110 1452 070 x 052 1432 110 1453 071 x 047 1432 110 1450 070 x 042
54. trongly discouraged for a street driven vehicle Dirt and varnish will accumulate in critical bleeds and upset the fuel metering Dirt and debris may easily get into the fuel bowl through the bowl vents or larger bleeds and cause a multitude of problems Any calibration testing should be performed with the air cleaner in place Depending upon the air cleaner used the metering typically will be leaner with the air cleaner in place Alarge 14 x3 open element air cleaner such as Edelbrock Elite Series Signature Series and Pro Flo air cleaners offers almost no resistance to air flow Flow bench results show virtually no reduction in air flow Also this design should cause no change to the fuel metering A10 x2 open element design will result in some definite air flow restriction but little change to the fuel metering Elements smaller than 10 x2 are more restrictive and have the most effect upon metering The fuel metering at WOT will be shifted LEANER especially at higher rpm ranges e Ifyou have a dual purpose vehicle that is sometimes used in competition without an air cleaner it may be necessary to have two separate calibrations If you are running a smaller air cleaner and have optimized the WOT with it in place do not be surprised to find that the metering shifts RICHER when the air cleaner is removed This may require you to calibrate the WOT with leaner Jets and Rods at the drag strip e DO NOT allow the vehicle air stream to b
55. you re done e If test 3 is slower than 2 change to 1 stage rich for the Primary and Secondary and you re done If test 3 is still faster than 2 go to 3 stages rich Primary and Secondary and keep going richer until there is no change or slower in the times Stay at the first no change level so that you stay with the richer of any two levels of calibration that have the same power Case 2 Slower than base calibration Go to 1 stage lean Primaries and 1 lean Secondaries and perform acceleration test 3 If test 3 is the same as base calibration go back to the base calibration e If test 3 is faster than base calibration go to 2 stages lean on both the Primaries and the Secondaries Keep going in the lean direction until there is no change or slower then back up 1 stage richer so that you stay with the richer of any two levels of calibration that have the same power Case 3 Same as base calibration Do not be surprised Change back to base calibration CALIBRATING THE PART THROTTLE The Metering Rod feature used in the Edelbrock Performer allows easy calibration of the part throttle without change to the WOT metering Cruise Mode The power output is low as in a steady cruise light acceleration Manifold Vacuum is high and the Metering Rods are down in the lean position Power Mode The power output is high as in a heavy but not wide open acceleration Manifold Vacuum is low and the Rods are up in the rich pos

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