[jrod92]

I checked my sparkplugs the other day and when i looked at them they were kind of white and burnt. I have GT-40 heads and am using autolite 764. i was wondering if i should be running a colder or hotter plug than this. Or would anyone recommend a different brand or type?

 

[GhostDog 5.0]

I use to run 764 on mt gt40p heads. They worked great. How old were the ones you had on there?

 

[jason91notch]

spraying n2o to it? if so, go with 1 to 2 steps colder, depending on how much youre spraying

 

[jrod92]

I use to run 764 on mt gt40p heads. They worked great. How old were the ones you had on there?

I think they have about 30,000 on them. Im not running nitrous or anything.
just performer rpm intake, gt-40 heads, x303 cam, 30lb injectors, long tubes. Isnt the thread lenght shorter on sparkplugs for gt-40 heads?