Overheating Issues, Perplexed

[elmariachi]

Originally Posted by Jerry Clayton

does your demon carb have the idle eze adjustment feature in the center of the base plate? the mixture screws on just about all demon carbs that i have done anything with usually end up around 1 1/4 turns out---

And where would you suggest the Idle-Eze be set?

Originally Posted by Jerry Clayton

you seem to be quite attached to the theory that it ran ok on the dyno and before the body was on the car----so what----forget that nd work on what you have now--runs hot---no dyno involved
To borrow some words from one i've never met---if the facts don't support your theory, get a new theory( Al Nunley)

I am not attached to it as a theory, its the facts. Do you have a recommendation?

[jwd]

I will add one thing about your timing. Now I'll admit I've never even owned a FE motor However, I've built and tuned many SBF, 460's,SBC and BBC some putting out over 600 HP and from where I stand, those timing specs. listed above are way out of line. What I shoot for is around 10 initial with a total of 36-iron heads and 34 for alloy heads all in by 2800RPM. You absolutely MUST have a dist. with vacuum advance that adds 8 dist.(16 crank) degrees and have it hooked up to a constant vacuum source. That will give you a total of 26 at an idle yet still be easy to start. The advantage of this set-up is better throttle response, better gas mileage AND a cooler running engine at all RPM's. I've never seen a motor that didn't run better with vacuum advance.
Jim

[elmariachi]

Originally Posted by jwd

You absolutely MUST have a dist. with vacuum advance that adds 8 dist.(16 crank) degrees and have it hooked up to a constant vacuum source. That will give you a total of 26 at an idle yet still be easy to start.

I'd like to hear other thoughts on this from the FE crowd. Anyone running this setup?

[ERA Chas]

Originally Posted by jwd

The advantage of this set-up is better throttle response, better gas mileage AND a cooler running engine at all RPM's. I've never seen a motor that didn't run better with vacuum advance.
Jim

And what do you do when your idle vacuum is 7" with a 250+ cam?

[jwd]

Originally Posted by ERA Chas

And what do you do when your idle vacuum is 7" with a 250+ cam?

Well, if you have a MSD dizzy, you can use a GM vacuum advance unit (that's all MSD uses) part.# vc 1807, 1808, 1809 or 1812 depending on how you want to fine tune your timing curve. All of them start at 5" of vacuum and are all in by 7".
Vacuum advance is one of the most mis-understood parts of an engine and my guess is that 99% of those out there have no idea how to properly tune an engine for the best performance.

Jim