What kind of effect will replacing the stock plugs on an 05 GT with the next colder heat range have. Is there a substantial loss of power? Would this create a tuning issue? Just Curious.
I have a JLT CAI/SCT Xcal2 combo. I've already pulled out 4 degrees of timing at the appropriate RPM range(4000-6000 RPMs) the detonation went away. I was wondering if replacing the plugs and advancing the timing might be a consideration