P-Head review

[tmoss]

Sweet...so you got it back on the dyno with some additional tuning since the 257 pull? Looks like a 20 HP and 20 TQ gain, well done!

Yes I did Troy. I'm awaiting some Jim Miller 1.70 rockers and a full-load adjustable push rod and I'm gonna get the valve train set up just right this winter and redyno next spring. We'll see how much the vavle train "blue printing" and the 1.70 rockers are worth.

 

[shewitt]

from what i have read that it wasent a good idea to go with 1.7 with p heads

 

[tmoss]

It's not that it is a "bad" idea, the flow on the stock P heads levels off around .400" lift and stays pretty even to .600" lift. Putting higher ratio roller rockers can gain some effective duration (at the valve) if you can take advantage of it, and my heads might be able to since they have valve seat depths and undercut valve stems - I'm gonna see. Also, if the geometery can be improved you can see a gain also. This is my final step in trying to optimize this setup.

 

[95snoozer]

where did your Ps peak at and hopw far did they pull to?

i am going to spin these bad boys up as high as i can go

 

[95snoozer]

I LOVE the GT40P heads, I mean what is there not to like. If I knew I could run them with a turbo (I'm worried about the header clearance issues) I would put them on my '90GT turbo project.

my friend ran a turbo kit on his fully ported p heads

i forget which kit though

I think it mah have used flipped p shorty headers

 

[Killercanary]

my friend ran a turbo kit on his fully ported p heads

i forget which kit though

I think it mah have used flipped p shorty headers

REALLY?!?! That's GREAT to hear. I just didn't know for packaging reasons if it would fit with the P specific headers and the turbo. Thanks!


P.S.- did you upgrade your valve springs on your P heads since you plan to rev it?

 

[tmoss]

My torque peaked at ~4,000 rpm and HP peaked at 4,800 rpm and held flat to 5,400 rpm.

 

[OrangeMustangGt]

woah, damn i guess that just shows the potential my combo may have., when it s tuned

 

[shewitt]

Im installing a novi 1000 now so i hope i dont have any problems from the heads some people say p heads are no good for superchargers

 

[95snoozer]

REALLY?!?! That's GREAT to hear. I just didn't know for packaging reasons if it would fit with the P specific headers and the turbo. Thanks!


P.S.- did you upgrade your valve springs on your P heads since you plan to rev it?

I have some comp doubles with new locks and retainers, or I will run the oens that are on teh e7s right now.

oddly enough i ran into my friend with the turbo car today. fully portedps with ferra valves he will be selling when his afr 185s are done.

I will ask him what kit he has on wednseday in economics class

 

[95snoozer]

Im installing a novi 1000 now so i hope i dont have any problems from the heads some people say p heads are no good for superchargers

thats bull you will make more power with less boost because of the higher compression and it wont be as much of a dog on the low low end off boost driving due to the raised compression.

of course keep the tune safe so head gaskets are not an issue

 

[shewitt]

ya i dont beat on the car that much but before the head change i could keep up with a vett now with this head change i was racing a rouch 03 or 04 and i could keep up with him and slowley pull away from him. The only thing was traction his tires were so big in the back he could hook up but when i did i would catch him

 

[OrangeMustangGt]

yeah, from what ive seen, with a correct tune, and supporting components, people are making comparable power numbers to alum heads!! now, this is with everything perfect, but damn for so cheap, you cant go wrong, and i guess ford really did try with threre last go on the 5.0 motor trying to get it to pass strict emmissions.

 

[l.groves]

The thing flat hauls with the cower cam and 1.7's. Just put a 70 TB on her a week ago and she now pulls great on the bottom and then the cam kicks in with my torque convertor at about 2500 and slaps you back in the seat until 5500 rpm. Still have a few issues as per my post earlier but over all very very satisfied with the P heads. Mine are a little modified though...

 

[fiveotony]

Since I grenaded my engine I am selling my P heads so I can up to the aluminum heads oddley enough I do not think the new heads will make that much of a difference from the old setup.