Small problems with 402 conversion
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Teching In
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Small problems with 402 conversion My project for the last year has been putting a 402 (bored 396 not an actual 402) in my 1983 1/2 pickup. I thought I might have problems going from the old diesel to gas but it hasn't been that bad. I've bored the block, ported the factory heads, and bought a cam and a new hei distributor. But I can't get it to fire. Is the something I may be forgetting? Also it has an inline pump and regulator and it's at 2.5 psi does that need to change? I believe the wires from ignition to starter are correct. And the cam I put in it is a summit brand sum-1797
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Teching In
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It turns over I have spark I have the 12 volt wire on the hei and I can turn up regulator but it moves a ton of fuel at 2.5. It need to be between 5-6 psi correct? And it's a 750 Carter I believe
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I believe so unless someone else (I have a lot of dumb friends that hang out in my shop) but while assembling this motor some time ago I made sure everything was right and it was months after that before I got the hei distributor and just set it in assuming it was how I left it
A common mistake is that when people put a cam in dot to dot they leave it there and stab the dist in the #1 position. that is wrong, dot to dot is on the #6 firing position BDC or also called "180 out". do as above stated and pull the #1 spark plug and put you finger over the spark plug hole and bump the motor over with the starter, it will blow air out the hole. then by hand turn the motor to TDC (#1 firing position). Pull your dist cap off and see where the rotor is at
Thread Starter
Teching In
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A common mistake is that when people put a cam in dot to dot they leave it there and stab the dist in the #1 position. that is wrong, dot to dot is on the #6 firing position BDC or also called "180 out". do as above stated and pull the #1 spark plug and put you finger over the spark plug hole and bump the motor over with the starter, it will blow air out the hole. then by hand turn the motor to TDC (#1 firing position). Pull your dist cap off and see where the rotor is at
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Teching In
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Still not working You guys were 100% right I was 180 off. But now I'm even more confused. It turns over faster than **** and it actually sounds like it's running but when you let go of the key it's still dead. Not sure what to do its so close but won't run
Thread Starter
Teching In
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A common mistake is that when people put a cam in dot to dot they leave it there and stab the dist in the #1 position. that is wrong, dot to dot is on the #6 firing position BDC or also called "180 out". do as above stated and pull the #1 spark plug and put you finger over the spark plug hole and bump the motor over with the starter, it will blow air out the hole. then by hand turn the motor to TDC (#1 firing position). Pull your dist cap off and see where the rotor is at
So it's timed now and I had a friend with a 460 who's carburetor took a ****. So I said screw it throw on the Carter I had on the 402. Turns out it would not push fuel through and it wouldn't run. So I took it apart and cleaned it and threw it back on, and wahla boom runaway 460 on the first crank so screw this junk carb I'm finding a new. It was also like a 750cfm what should I be running on this mildly built 402?
Teching In
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From: Lincoln, Ne.
Last that I looked, Holley was recommending double pumper carbs for lighter vehicles like Camaros, Mustangs, etc. For full size cars or heavier vehicles they recommend going with a single accelerator pump carb. That distinction was somewhere in their catalog along with a short explanation of why.
Launching!
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My experience has been that the double pumper is better...always. The bigger the engine (or more radical the cam) the better the double pumper will be. The single shot just can't make up for the secondaries opening. The only way to overcome it is to slow the opening of the secondaries and live with less performance.
