I am looking to buy a set of heads for my 1995 f150 ext xlt model not a lightning. I want to take off my stock heads and get a set of either gt40 x or p heads. Would both the x and p heads work on my 351w, if I had the head bolts drilled out to half inch would I be able to put either ones on. If so what is the bolt on power from a ported and polished gt40x and the gt40p ported and polished. Please don't waist my time with stupid comments. Thanks

 

Go for it and see what happens. I don't know what the results would be. but if it were mine I would leave well enough alone because the 5.8 is already a decent power plant.

 

Well it has power but for 300 bucks for heads that can bolt on 60hp that's a 210hp increased to 260-275hp. But I still want to know which ones better.