guitarcrazy02

So I just put in my new engine in my 1981, a 290 horse 4 bolt main 350 from GMPP.

Specs:
8.5:1 cr
76cc iron heads
1.94" intake and 1.50" exhaust valves
.450/.460 lift cam @ 222 duration

Reused:
Stock intake manifold
Stock QJet (original replaced by a 1980 to compensate for CCC)
Exhaust Manifolds
Distributor (no advance, mechanical or vaccuum, since CCC removed)

Here's the dilema: I cannot for the life in me get it to idle properly. I am aware of the distributor problem. I replaced it with a good old fashioned HEI unit with vaccuum and mechanical advance that I got from a friend. The vaccuum doesn't work, but I can always replace that. That shouldn't effect idle though, should it?

Everything emissions-wise is gone. A.I.R pump gone, EGR valve is in place, but not connected. All unnessecary selenoids and electrical garbage is gone. I've eliminated it all and it's running like any pre-computer car should, except for the idle problem.

Also, I've had the idle set all over the place on the carb, too. I've also monkeyed with the air/fuel mixture, and still, the same problem. There aren't any vaccum leaks as far as myself, my dad, and his mechanic friend can see. It's got all 3 of us stumped.

My question: Has anyone else ran this combination I have? I couldn't possibly see that my cam is too big to allow it to idle properly. I'm stumped. Don't let me down guys, I know someone can help.

guitarcrazy02

shoot i put this in the wrong forum. If a mod sees this, can you move it to Tech/Performance.

Matt Gruber

vac advance needed for decent idle- hooked to manifold

Vette Crazzy

set the timing at 36 deg at 3000-3500 rpm... and go from there


vc