how do the gt 40 (not 40P) heads stack up? what size valves? use normal headers and spark plugs? screw in studs and plates? good flow? might have a chance at a set. are they worth it? cast iron, by the way thanx in advance.
I have a set off of a 95 cobra. Dont know the specs but they will flow a lot better than my stock heads. That's what my engine builder said. He also said that they will support a 400hp motor with porting done. GT40p is the heads that came on 93 Cobra witch is one of the faster cobra's they came out with until the lastest Cobra's came out with the 4.6 engine. I have not complete the engine yet but plan to have a 300hp at the rear wheels with porting done to the heads.
Actually, all cobras came with standard GT-40s. The p's come on Exploders/Mountaineers after '96. I would rather have standard GT-40s over p's any day. GT-40 heads should give you between 20-40HP over stockers depending on the combo. AC
AC is right. GT40p's are a headache. They need special headers or for Mavericks & Comets custom headers. But I did find a company that sell the headers for early Mustangs. They might fit our cars but they didn't know for sure. GT40's are easier. They did come on SUV's too. I forgot.
