Thread: 350 idle problems help please!!! holley 670

Tweet

hello any info is greatly appreciated! i have a 91 camaro with:
350 +060 line honed melling high volume oil pump stock crank pink rods hyper 9.3-1 flat pistons, sr world product heads ported polised 1.94 1.5 melling 246 246 @.050 .510 .510(2 big gunna switch next winter) the cam is advanced 2* matching valvetrain,accel cap n rotor and a supper coil 8.8mm accel wires edelbrock rpm rebuilt holley 670 street avenger 3200 stahl 373 posi rearend

ok here is the problem the car starts fine even idels fine (we can get it to idle at 350rpm in park after messing with the idle speed) the problem is cold or warm in park it will idle at 2000rpm and when put into gear it falls on its face and either chokes out or if i give it gas it will idle but then fall off (we had a edelbrock 750 with no choke last year and had same problem but not nearly as bad) the initial timing is at 15* we have at 2000rpm 14lbs vacuum and at 800rpm 4lbs of vacuum(we r getting a vacuum booster can soon)

please help haha this is my first hot rod im building it with my father who is a hot rodder (gm) but hasnt played with um in a long time. haha we really appreciate any help:-)

thank you adam and eric

At 4 vacuum your power valve is most likely active at idle. It will never idle correctly with the PV draining fuel into the carb. Standard power valves are usually come in at 6.5. Looks like you need a 25 PV. Better yet do the cam swap now.

Kitz

Kitz is right about the PV. Put a 2.5 in it. With this much cam, you also need more initial timing. Go with at least 20, with the total centrifugal all in by 2800. Plug vacuum into the manifold, not ported at the carb. If the starter kicks back on starting, interrupt the coil wire and install a momentary off switch. Push the momentary button, crank the motor to bring it up to speed, then release the momentary button and the motor will fire off. No sweat.
Also, check fuel pressure at the carb. No modern carburetor needs more than 5 psi pressure. More pressure than that WILL NOT MAKE MORE HP, it will simply over-power the needle and seat and blow raw fuel into the intake manifold.

hey i guys, thank you very much with the advice, i have orderd a 2.5 holley power valve prob get it mon, we put heavier springs in the dist and that seemed to help some, also we forgot that the cam has 4* built in and we advanced the cam 2* more trying to pick up on low end. stoped at a hot rod shop and talked to a couple guys who said i need to back off the dist and adjust the idle speed accordingly. any thoughts???? i appreciate it every1!!!