Hello Everybody It's time to change my spark plugs and was wondering what brand and heat range I should be useing for my combination. It's a 70 GS Stage1 with Gessler Ported heads intake & exhaust manifolds. Popualar Mech.230/245 cam. Quadrajet off of a 71 455 gone over by John Osborne. 3in. X pipe going into 2.5 mufflers & tailpipes.Currently I am useing AC plugs for a 70 455. Thank You Bob
Other than the AC's, I've heard that Autolite 24's were pretty good plugs to run. Coincendentially those are the same plugs that my F-150 takes.
I really like the Champion RV17YC. It is a projected nose plug and it puts the spark deeper into the combustion chamber. My car just feels snappier with them. I've tried AC R43TS and Autolite 24's, and I keep going back to the Champions. They really seem to resist fouling better than any other plug I've used, not that that's a problem anymore with my MSD box.