Gt-40 vs. GT40p vs. GT40X
 

Hey guys, i would like to get some new heads for my stang, as i know these really open it up. I am very interested in getting some GT-40 heads, but what is the difference?? Gt40 Gt40p and GT40X? What is the diff? GT40p's came on explorers right? Also, how much HP would i be looking at with a new set of heads, in a gain wise. THANKS!!!

Not an expert, but ..
 

GT-40 - Old school iron heads.
GT-40p - Newer school iron heads. Better plug placement and needs correct headers because of plug placement. Smaller CC than the GT-40 for higher compression (if you need or want more compression)
GT-40X - Aluminum heads

Check here for flow numbers

Flow Page - Good Stuff

Good luck.

ok thanks