Gt40 heads on 351w
#11
#15
I wouldn't expect more than 20hp, the 93-95 lightnings were only rated at 240hp. I think they are probably about 1/2 between a stock E7 and a enrty level aftermarket head. I know I could tell a difference when I switched from GT40 to Edelbrock RPMs and it showed on timeslips as 2 tenths in 1/4 mile. The 3 bar GT40s are hard to find in explorers, I look everytime I go to a pull your own parts yard and I would say 8-9 out of 10 have gt40p heads. I personally think that they might have been using the gt40p heads prior to mid 97, but mid 97 is when they had absolutely no more regular gt40s left.
Last edited by tj78; 03-21-2016 at 06:41 PM.