I am running a 408 LS with LS3 heads 12.5 compression on E-85 . Currently using TR6 plugs that are extended tip . Just wondering what other racers are using . Car is running 6.02 3000lb Regal
I was told that non projected tip 7's are the ticket for just about everything. Well guess what my car runs better with projected tip 6's and the plugs stay cleaner. I have a little different combination, It's a street strip 408 ford motor with 12.5 comp but I would say 6's are fine for your combo. As with everything, you just have to experiment. My car starts easier (especially in cold weather) and runs better with the 6's. Oh yeah not a lot of help on this board but it has some good information. Good luck!
Ford 408,Proform 850, AFR225 heads, 12.5:1 Comp, TFS Hydraulic Roller, Kooks 2" Headers, PA C4 Super Comp trans Edge Racing Converter, 3.55 Gears E/T: 6.40 @ 105.10 (1.37 60')