I'm running a sbc with a three holley 94's and a points style distributor. Carbs are fresh rebuilt, everything in the ignition is new, and the fuel pump is new as well as the gas tank. I've got the idle set at about 750 to 800 in neutral and it sounds great with good pedal response. The problem is when I put the truck in drive, the idle drops down to about 400 rpm and wants to die out. If I set the neutral idle to about 1000 rpm, drive drops the idle down to a more managable 550 to 600 rpm. Why is my idle dropping so much when I put the truck in drive. I have a stock torque converter with a TH400 trans. Any ideas anyone?
Where do you have the vacume advance hooked up to? If into manifold vacume methinks that is the problem. If so block it off temp. and reset the idle and see what happens.
sounds more like a trans issue to me..olskool53 may have hit on it. or you have a bind in your trans. and what Bishop said too.
No, stock cam. Vacume advance is hooked up to the manifold, but there is no spot for vacume advance off the carbs unless someone knows a way to tap into holley 94's. Torque converter was my first guess too, thanks guys. Any other ideas would be great!
there was a thread on here not too far back where a guy was having a simular problem. He would set the idle and when he put it into gear it would almost stall out the engine. If my feable memory serves me correctly his problem turned out to be Trans related and torque converter problem. a new one solved his issue.
Try eliminating vacuum advance altogether and use mechanical only. Manifold vacuum does not do well for advance purposes. Just set your initial timing higher to begin with. Won't cost anything to try.
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