The GT40P heads will whoop the GT40 Irons in low, mid, and hold right equal with them under high lift.
There are a ton of differences between the P and the standard GT40 heads. Different exhaust valve, revised port designs, combustion chambers, nearly non existant thermactor bump. It all makes the P a hell of a lot better.
Onto the price. If you can't find a set of GT40p's for around $400 you're crazy. $700 is WAY too much for a set of iron heads IMHO. With a little shopping you can find a set of TFS aluminums for around $1000 right now.
The Windsor Jr's are unimpressive as far as their low and mid lift flow numbers if you ask me. They are very linear in their increases.
|