GT40/40P castings are identical with the exception of the spark plug location/angle to improve cylinder combustion and emissions. We're talking nickles and dimes as far as power difference between the two.
Missed the point? There is nothing that Ps have that a regular set can't have, if money is an issue then you work with what you've got. I've got money that says either head will get you in the 12s.
Go here http://www.stangbangerz.com/ and you'll find a few hundred guys running deep in the 12s on both heads, and they don't talk chit like a lot of people do about parts that they've probably never ran. Like i said in my earlier post....two cars, nearly identical builds with the exception of one having regular GT40s and a stock cam, vs. a GT40P car with an E cam, and they ran within TENTHS of eachother, and we're talking 1-3 tenths back to back. The P headed car was even EFI and tuned, so with that and the cam vs. the other car with a vaccum secondary 600 carb and all junkyard parts...you tell me, what point did i miss?
Missed the point? There is nothing that Ps have that a regular set can't have, if money is an issue then you work with what you've got. I've got money that says either head will get you in the 12s.
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