I was thinking of running these Autolite racing plugs . Autolite AR3910
They are for engines in the 12:1 range. My current set up will be at 12.3:1. I'd like to run a direct port 300hp shot, eventually. Who can recommend some good plugs to run , now, NA. The nitrous won't come till I have a Dana S60 and 10 point cage in the car.

 

I like the Zex plugs. Tried alot of them (NGK/ Autolite). These worked for me. Not easy to fowl. App... 97ss M6 383 D1 meth/ H2O.

 

ZEX? like the nitrous zex?
I've seen charts for spark plug applications and they always seem to have the nitrous plugs different than the N/A plugs. Is this due to the plug having a shorter strap?

 

Comp Cams owns the Zex name. My app is FI. Found them on the Zex web site. Under 6 dollar per plug. They have 3 additional ground straps positioned on the porcelin, and, claim they run alot cleaner. They have worked well for me, and, do not fowl easy like the single ground strap type. Copper core with nickel plate.