Hello everyone my question is whats The best spark plug to use for my GN1s that are fully race ported & will be run at @ 28lbs Of boost and what to gap them at. I'm using a 6870 Turbo with 93 n alky on my 4.1. Thanks guys
I can answer part of your post with my opinions that our preferred brand is NGK, a gap about .028-030", and not to use a projected tip plug at that boost.
As far a heat range, you need to find the specific plug number by trial and error, starting with a cold plug and move up with the heat range determined by reading the plugs after checking after many passes to view the plugs, at least one or 2,
If you do not know how a proper plug should look, do a search to obtain this necessary info to protect your expensive build so you can depend on yourself, not someone behind a keyboard like me!