I have a 351W 12to1 comp pression with Edelbrock Vic Jrs. heads if any of you guys and i know you are running these heads what plugs are you runing i have been running auto lights 3924 it recomends that i run a champion C57C i seen a autolight crossovers and that plug looks way to cold to me i run 112 octane racing fuel and i think it still detonates a little i cant here it, it is a strip only car 88 mustang coup but from looking at the plugs it looks like it is detonating i just want to know some brands or part numbers other run.
the NGK's are about 2 steps colder plug with out the projected tip i will try these and if I still have any detonation I will try the Autolight 3933
I will see if i can post a photo of my spark plugs that i have been using
I just got a set of Denso Iridium Plugs for my 2004 Ford Focus, and I think they are great. I noticed a slight power increase just from the new plugs. I gapped them to the car's specs under the hood. If you are wondering irdium is 8x harder than platinum. If you used the proper set of them, you probably wouldn't need a new plug for quite some time. Check them out at: