Any one Know what a good vacc reading is
on and OHC six x 4 bar

Thanks bill

Looking at the AMA specs for the six cylinder engines, the maximum vac advance is 15deg at 10.5-11.5hg. On my 400/4bbl, I have 15-16hg with engine in drive (650 rpm).

My '66 Le Mans Sprint OHC6 4 bbl pulls 18-20" at warm idle 650 rpm. It depends upon your cam.

... and your compression ratio, and your ignition timing, and your air/fuel ratio.

I am running the H cam and 69 ohc carb
the problem I am having is the engine is hunting
for a smmooth idel

I think the power valve is to strong with
15" of vac

the motor sounds like a 8 cylinder from the rear

any thoughts

bill

with the Quadrajet, the primary power piston spring is what you want to work on. You need to clip it or replace it. Drop a plastic straw down the front bowl vent and see if it rises and falls at idle with the engine surge. Then hold it firmly down and see if the idle smooths. If so, get a spare spring and snip 1/2 coil at a time and test until you get a smooth idle.