Holley Idle Screws Not Responsive

GeorgeGerhard said
Hello 684mulas
You mentioned you purchased a MSD Probillet dist. Is that not a mechanical advance unit?
I was under the impression that unless you are all out racing a vacuum advance is recommended.
I would appreciate your comments
thank you
George Gerhard

Yes, George that is true but I know quite a few other guys that are using the straight mechanical unit and it works fine on the street if its setup well. The vacuum would probably get a little better gas mileage but I don't expect good gas mileage with this car no matter what I do.

JoeDust451 said
You can get away with no vacuum advance if the int/total & curve is dialed in, & the carb is set up right in the curcuits, not too rich, not too lean.

684mulas, i would set up that carb for 4 corner idle, this will give you alot more adjustability, with that cam, 18 & 36 should be very close.

The 750 DP that I have does have the 4 corner idle. Now that the screws actually do something, I was careful to make the best use of them (even used a vacuum gauge to get everything setup). The primary idle screws are turned out about 1 full turn and the secondaries are about 3/4th turn. The vacuum is about 12-12.5" and it has a 6.5 power valve. I didn't touch the jetting it came with 71/80.