trans_am7935

iTrader: (15)

i have put about 5k miles on my car since a cam swap, and had the spark plugs for about 22k - 25k miles. the plugs are NGK TR55. dont notice any problems and dynoed 440 about 3 months ago. before i go and pull them, how often should these things be changed with a cam and 11.2-1 compression?

Stippy17

iTrader: (5)

Your going to get mixed answers. Some will say to replace them every 15-20k, and some will say you can take them to 50k.

Im one of the ones that replaces mine every 15-20k. If it was a daily driver that didn't see much abuse I might leave them in longer, but its a daily driver that sees regular abuse haha.

The best answer I can give is pull one or two plugs and examine them.

trans_am7935

iTrader: (15)

yea i drive mine 1-2 times a week, some times not at all. but when i do i like to rev it up there a bit, especially on the on ramps....natures little race tracks!

trans_am7935

iTrader: (15)

here are pics of #1 cylinder on the top and #6 cylinder on the bottom in both pics




they are both pretty black, no white residue or anything, and the little "V" mark is still visible on the bottom copper piece. i have not checked the gap but they were originally gapped at .060

JUSTINSWS6

Im going to do mine every year. Which will help with mine i have a higher cr