Hey guys. I run a 500" Indy motor in a A body. 440-1 heads, Indy 440-2 intake. With my 4150 series carb It's a steady 5.95-6.05 @112-ish car depending on weather & track. Typically a 1.37 or lower 60'
I wanted to go to a Dominator. So I borrowed an older 7320 Holley and mounted it with a Wilson Manifolds open adapter 1.5" tall. When I fired it early this past spring it fouled #7 plug almost immediately. So I put my 4150 back on and it was good to go. Last weekend was running 6.01 on the 4150.
In the meantime I ordered a new custom dominator from a well known builder. Not saying who right now because I don't need all those carb builder loyalties to come out.
So this past week I put on the brand new dominator. Again with the 1.5" adapter. And guess what? #7 fouling very quickly. Plug doesn't look all that bad but I'm checking them at idle with an IR temp gun and 7 is at 200° while the others are above 500°. Here's a temp check at idle aiming the beam right at the tube about an inch or two from the port.
Exhaust temp check videoI'm running Autolite AR3910's, MSD box, with 35° timing
Any thoughts or guidance on correcting the issue? I'm open to suggestions.
-Thanks