hey guys been doing some research and was wondering, which head is better the GT40 or GT40P? I cannot seem to find this info. what are the differences? thanks
In your Mav, the GT 40 heads work very well, the GT40P's have a problem with spark plug /header clearence.
Ill add somemore info, you CAN use the gt40p heads BUT you can only use stock manifolds. Edit: miss informed by a member (not going to mention any names)
Uh, no. I ran an old set of Blackjack headers on my P heads. Had to use Accel shorty plugs on the driver's side and short 90* spark plug boots. Used a cut down plug socket and had to loosen the headers to get at the plugs. The P heads flow slightly better than the GT40s but it is a hassle dealing with the plug issues.
I did the same as above, with a special spark plug tool I made by cutting the socket down, and then cutting away 2 flats worth of material on the side, so you could slip on the plug from an angle. Also, I ended up taking a second header flange and gaskets on both sides, inserted it between the header and head for a little extra space. The 90* hei boots were still melting so I needed to put more space in there. Those accel shorty plugs for these heads are $16 each. So there is another setback with P heads. And you NEED them. I finally found that it was just less time consuming to jack the engine up, remove all the header bolts, and move the header out of the way to swap plugs. It is THAT much of a hassle. Other side is fine and quite easy to get to the plugs.
Here are some pictures to get a better idea of what we are talking about. The plug tool... Driver side mockup showing where the plugs hit. They DO hit, it isn't just an optical illusion from the angle of the shot. Those hit dead onto the center of the header tube. But then here is the passenger side head. No problems at all.
Hey Thanks for the info ...especially the pics!! guess I wont be getting the P-heads... too much hassle for sure. I thought the spark plugs were a PITA with stock heads! I cant imagine with the P's! forget that! lol
Yeah, you said "Ill add somemore info, you CAN use the gt40p heads BUT you can only use stock manifolds." Misinformation. Scooper and I provided examples that headers can be used, so the statement "you CAN use the gt40p heads BUT you can only use stock manifolds" is incorrect.
Oh, ok. I read it wrong lol. I thought you were saying i said headers (Which makes no sence at all, any who, your right i was wrong.)
