[r hammons]

having a rich idle problem (fouling plugs)running a 60 over 400 turbo 400 488lift 320 dur cam 750 holley dp have 71/76 jets 8.5 pv in front rear is pluged,, runs very rich at idle . have had carb apart found nothing wrong, when tring to adjust idle the mixture screws have no effect on idle , have drilled holes in all four throttle plates , had very little effect,if and when you get a desent idle , i get a bad stumble off the line, motor is pulling a 10 on the vac guage, have checked the position of the throttle plates seems to be ok?, down the track car runs fine , ran a 11.95 at 111mph with a 1.64 60 ft at darlington sc today temp in the 70s does show a little black smoke off the line all advice greatly appreciated, thanks

[r hammons]

having a rich idle problem (fouling plugs)running a 60 over 400 turbo 400 488lift 320 dur cam 750 holley dp have 71/76 jets 8.5 pv in front rear is pluged,, runs very rich at idle . have had carb apart found nothing wrong, when tring to adjust idle the mixture screws have no effect on idle , have drilled holes in all four throttle plates , had very little effect,if and when you get a desent idle , i get a bad stumble off the line, motor is pulling a 10 on the vac guage, have checked the position of the throttle plates seems to be ok?, down the track car runs fine , ran a 11.95 at 111mph with a 1.64 60 ft at darlington sc today temp in the 70s does show a little black smoke off the line all advice greatly appreciated, thanks

[Carl]

I think the power valve you have is too high. I would try a 5.0 or 5.5.from what I understand take the vacuum reading you have and divide it by 2. Then get a power valve that matches that amount. Hope this helps. [img]/infopop/emoticons/icon_biggrin.gif[/img]

[Tom Vaught]

r hammons,
Please call me Tom Vaught (e-mail me for number)
I know what is wrong with your carb. I fixed Tim
Cockeran's over the phone, I can fix yours the same way. Tom V.

[RPM]

Could you also post what the cause/fix is? Thanks

[Lemans1]

Please?

[r hammons]

thr problem was that i was solving one problem by creating another problem , i was adjusting the idle screws out to cure a stumble off the line ,this caused the rich idle/plug fouling problem, the cure was to ask for advice (thanks to allfor your advice)listen to what they had to say , which was to adjust the idle then work on the stumble problem which was solved by working with rhe pumps and squirters, THE PROBLEM IS FIXED i have a clean idle, no stumble off the line and clean plugs, now i have a little popping through the exhaust when i am slowing down after a run, not while accelerating, think i might be a tad lean ?

[RPM]

Ok, great! Thanks for posting the fix. Popping on decel could be from air entering the exhaust system and/or rich condition using the engine as a brake.