Idle raises when warmed up?

[72cudamaan]

 

[422STROKER]

I was thinking as your beast motor warms(smooths) up it's making more vacuum thus bringing timing in on the manifold vac port and raising rpms?  Just a thought.

Tom

[jhaag]

wondering the same on the vacum connection. even if it doesn't fix the problem it needs to be connected to ported vacum, otherwise at wide open throttle you have low or no vacum. that defeats the purpose of a vacum advance. dist connection needs to be above the throttle blades.

[422STROKER]

At WOT there won't be any vacuum either way(ported or manifold).  Some use the manifold vac to add some initial timing at idle to smooth out some issues. fwiw.

Tom

[dodj]

I thought  mopars ignition/dist were engineered around manifold vacuum? 36*-38* total at 3000 and dial in/out needed advance at idle with the vacuum advance adjustment. 

[422STROKER]

AFAIK it's ported vacuum that way there is no timing added at idle.

Tom

[brads70]

I haven't had a chance to mess with it yet but I forgot to add I only get 5-6 inches of vac at idle?

[422STROKER]

Warmed up vs Cold?

Tom

[brads70]

Warmed up vs Cold?

Tom

About the same. I have to feather it for a minute of two before it runs on it's own due to no choke.

[422STROKER]

How about timing at idle?  Cold vs warm settings?  Check the timing at the warm high idle vs cold idle as the vacuum is connected.

Just bouncing ideas.  I assume you checked throttle cable for burrs and the return spring is sufficient to pull back.  Any vacuum leaks at intake or carb?

Tom

[jimynick]

How's that mean mother running, by the way? I imagine that it's a bit of a monster. Heehee! Watch out for the OPP! 

[HP_Cuda]

Yeah I was going to say vacuum leak as well.

Check it while cold and see what the delta is when warm.

Otherwise you may have one of those temperature sensitive springs on your throttle!!!

 

[brads70]

I'm pretty sure there are no vac. leaks , sprayed card cleaner around and found nothing. I'm thinking it's in the distributor. Right now we are in a deep freeze so I won't be starting it for awhile.