I'm questioning what the proper size of the outboard carb's throttle plate little holes should be. I'm running a 340 in a Challenger (T/A clone for street/autocross and road course lapping), stock cam (.429.444), mild head porting, 1 3/4" Hooker headers, Promax center metering block (64 jets) and f/r plates (80 jets), adjustable rear base plate. The idle seems to be the problem and a good racing buddy looked at the hole sizes and believes they are much too large (compared to some old used ones I have aside and there is a difference) -- maybe they had been drilled larger for use on a modified racing s/block ... from my memory 35 yrs ago when I bought the setup). We can change the plates to smaller hole-size plates and believe that could solve the problem. Any help on what the original hole sizes should be? I (we) are trying to make it run/idle, etc perfect!

Thanks ahead! I'm soon going to Road America and Joliet Autobahn to be their "Pace Car" for road racing wknds.

Mopar Mitch


Mopar Mitch "Road racers and autocrossers go in deeper and come out harder!"... and rain never stops us from having fun with our cars... in fact, it makes us better drivers! Check out MOPAR ACTION MAGAZINE, August 2006 issue for feature article and specs on my autocross T/A!