Ok. I'm having trouble setting the slow and fast idle on my 71 Olds 98. It has the 402194 cam in it with 308*/308* duration at .474"/.474" lift. It has the TRW 2323F pistons, and an aftermarket Summit HEI distributor.

I set my timing at 10* advance at 1100 rpm. Then I put the car in drive and set the slow idle to 800 rpm, any slower and it dies. Once I set the slow idle to 800 rpm I put it back in park and the fast idle jumps up to 1400 rpm. At 1400 rpm the car diesels when I shut it off.

I do this with the car hot at operating temp. The fast idle cam is also disengaged.

Is my timing too advanced or am I expecting too low of an idle for this cam? I am pulling 12" of vacuum with my idle mixture screws 3 turns out. I drove the car from the exhaust shop to the house (about 3 miles) this way and it didn't overheat or anything, but I was driving like a granny. I'm not concerned with off idle circuits yet since I can't get the idle right. Any suggestions?

 

Are you running the vacuum advance off a ported source? I always shut my cars off in Drive. Something I got in the habit of years ago from high idles and lumpy cams.

 

The vacuum advance will be hooked up to ported vacuum; however, I am setting timing and idle without the vacuum advance hooked up. It is capped off and I have no vacuum leaks.

I forgot to mention that I have an Edelbrock Performer intake manifold, and a 750 cfm Rochester Quadrajet. It is a 455.

 

Re-connect the vacuum advance before you set your idle and see what happens.

 

Thanks. Anyone else?

 

TTT