FlyinMSP said:After trying all the different plug material, I'm sold to Iridiums. We are having a VERY hot (and humid) summer and the only plugs that hold well for me are the NGK ZFR6FIX-11 (peak boost at 8 psi, steady at 7). Coppers didn't hold up. Unfortunatly, they don't make them colder, which is what you want with ur setup and climate. I would look at Iridium from Denso, more precisely the IK 22, which is equivalent to a "7" from NGK and is also pregapped at 0.32
PS: a more efficient intercooler would prolly help more....
My car runs very smooth at stock boost on the IK-22s. I will see how it runs with upped boost when I get my GT28rs installed this weekend.