GT40P Heads - How Much Performance Improvement?

Gents:

I have a 1994 PCM High Output "Pro Boss" 5.8 engine. 700 hours on the clock. I keep reading about people upgrading to the GT40P heads. What improvement could I look forward to if I were to add the "P" heads to the current configuration over the standard GT40 heads that I currently have?

JQ

To answer your question. PCM told me 50 HP.

But if your GT40's are cracked which many have done, the P's will will leave your wallet heaver than getting another set of plain 40's . Not many Fords came with 40's but every late model V8 Explorer and Mountaineers had the P's so they are easier to find.

I put P's on my '95 GT-40 motor because I had a crack in the original head, mostly because of cost and availability.
Can't really say if I got any more performance because I also changed the cam at the same time.
I can say that the combo netted me some nice performance gains, mostly hole shot and mid range performance. Can't seem to get it over the 50mph mark.
All that being said I wouldn't change heads unless you needed to, if your going to upgrade other parts for more HP there's much better power to be made from other heads for a few dollars more. JMO

I'm not sure how much merit that argument has, the PCM pyramids look a lot like shorty headers internally (there are cross section pics from Alan if you do a search). Only a few folks have built engines that want to spin more than 5200 or so for peak power, but that doesn't mean it couldn't be done. Even with stock exhaust.