Gt40 Sparkplug horror

autolite 764

BlackPearl955.0 said:

thanks I ended up buying autolite 3924

Click to expand...

those are for aluminum heads

I run ngk TR6 plugs, they are 1 range colder than stock.

stock plug for gt40 heads = a TR5

one range colder for a gt40 head = TR6

2 ranges colder and you have to run an Irrid. plug that is like a TRi7 or TR7i or something.

I had a HUGE PITA deal getting the correct plug at 1 range colder. I finaly got NGK's phone number and called. They were 100% helpfull. I have had good res with NGK plugs from cars to bikes. The autolight plugs are great too, I just was done with trying to get a damn part and had what I needed for a NGK plug and ran.