Carbureted LSX forum - fouling plugs

need help have msd 6010 on 5.7 99 camaro keeps fouling plugs holley 750 carb 70 ft 78 r truck coils

How far are your air bleeds screwed out and how much timing are you running

air bleeds are 1 1\4 turns tried all 6 chips and put in custom timing 28 max still fouling plugs idles fine but try to launch off line bangs out and dies plugs are black from gas fouling

How did you set your idle mixture, with a wideband, vac gauge or just set it and forget it? Holley's on an LS with a single plane intake tend to run rich unless you have modded the carb. Mine are a little over a half turn.

Could be a half dozen different things like a blown power valve, bad gasket, etc. But start with getting the idle screws right first. Obviously clean your plugs too.

i think my idle mix screws are close to 1/2-5/8ths of a turn out on mine with my wideband reading high 13's at idle

Weak spark can foul plugs too.

i think my idle mix screws are close to 1/2-5/8ths of a turn out on mine with my wideband reading high 13's at idle

Same here, my next step is to open the idle air bleeds...

im back got the carb back from carb guru reset the idle circuits and air bleeds internally put carb back on still turning plugs black four corner idle 750 dp tried setting air bleedsto1\2turn carb loaded up went back t o 1&1\2 idles fine just turns plugs black could it be bad cam senser weak coils wouldnt run rright would it

The MSD box doesn't need a cam sensor to run. It has a 50-50 chance of coming up right each time you turn the key. If it starts at all then it isn't the cam sensor.

This Guide (http://www.holley.com/data/TechService/Technical/Carburetor%20Tech%20Info.pdf) tells you how to adjust your idle circuits.

You went 1/2 turn from full seated and it loaded up,but 1 1/2 turns its fine? Something wrong there dude...