I'm going to assume that those heads use the 5/8 body .750 long spark plugs, if that is so I would start with a set of Autolite 3933 and see what they look like. My E85 motor has a little more compression than yours does and DOES NOT like the next step colder # 3932 plugs shruggy work
I've been told by several different E85 racers that E 85 does not need or like colder plugs shruggy
IHTHs thumbs

Last edited by Cab_Burge; 04/13/18 11:44 PM.

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)