A respected GT tuner is highly recomending the NGK 4177 as a great plug to run in my 2006 GT. Of course I'll need to replace it more often but he feels the engine runs better. Comments?
In my mind the only reason to deviate from the stock plugs would vary greatly on what modifications where done to the vehicle and the end use of the vehicle IE road racing predominately or street use ECT.
MNJason - Note that the starter of this thread is on permanent vacation. Your owner's manual says 100K. If you've modded the engine, then you need to talk to whomever did the mods.
LOL - just saw that. I have a stock 05 with 9k miles so guess I am safe! I was mainly wondering because the GT guys are here this week and I could add it to the list.
Guess I'm "Old School," but I try to replace mine every 25,000 miles. They look good when removed, but replacements are cheap enough to warrent a conservative philosophy.
I have a whipple and headers, I'm running 15Lbs. and had a misfire code and a bad misfire. I checked the plugs, they all looked good. I replaced them with NGK TR7IX iridium plugs and never had the problem again.