Was just wondering if anyone has tried these heads on a 351W? If so what do you think thumbs up or down?

 

its uncommon gt40p's have weird plug angles and doesnt alow for the use of normal headers

 

Some good reading in here: GT40P engine in Bronco - GT40P heads AND GT40P HEADERS that WORK - FSB Forums

 

Thanks, that was good information.
I rebuilt the engine right after I purchased the truck so my heads are fresh. I was just curious if anyone had first hand experience of putting them on a 5.8L. I would love to find a source for the preformed plastic vacuum lines. Mine are crumbing and I would love to put it back to a factory look instead of using rubber vacuum lines.

 

These are the vacuum lines I got for my truck. They are really nice lines. I made an attempt at building some hard plastic lines, but it looked crappy and I didn't like it. These lines should out last the plastic and be easier to work with down the road.

Silicone Vacuum Hose, Turbo Hoses, Vacuum Lines | Oomph Labs

 

im using them, they have smaller combustion chambers so youll bump the compression a tad (i milled mine for further compression bump). good amount on the exahust side that can be removed via porting, overall i was impressed by the quality of the casting.

just make sure your headers will work, thanks to smokin tatsch (posted pics of his) i could tell mine would work.

 

subscribed, just to hear results on GT40P heads...

 

Untouched P's flow 30% better than E7's so there is no way they perform worse, the only dowside is fitting headers and from what I gather that's not such a big deal either.

 

90* plug wires allow the p's to be used with virtually any Long tube header. I re-used my old wiress that have a pretty heavy angle to them, but I had to reverse 3 of them so the 90* boot (cap end) was on the header side. There should be no fitment woes whatsoever with 90* wires and p heads.

 

What setup are you running your P heads on? what long tubes are you using?? I'm planning on putting a set of P heads on my 351W thats going into my 1992 F250 2wd ... i really wanted to get a set of long tubes, but im scared for fitment issues. are you running standard length plugs or "shorty" plugs??

 

Ok, have never looked, but, if you wanted to run iron manifolds, could you use the explorer/mountaineer manifolds? I know the 5.8 has the EGR tube in the front, but do the outlets come anywhere close? The thought crossed my mind to use the GT40p's in my 86 5.0... My cousin has the truck now and there's no way in hell he'd want headers.

 

i hear the manifolds work but are EXTREMELY restrictive ... and you'd need a custom fab pipe

 

More restrictive than the stock 5.0 86 manifolds? The explorer was rated at what? 240hp or something? The 86 was only rated at 185 IIRC.

Welding's not a problem so a custom Y pipe isn't a big deal. Now that I found the Magnaflow Stainless Y pipe I'd do it all in Stainless and it'd be the last Y pipe ever needed.

 

I dont have a single car or truck, with the exception of my K car, that didnt eventually end up with headers ... and i always pick up both power and mileage ... that tells me theres always some restrictions there ...

 

I am probably one of the few on this forum that have actually run GT40P heads on a 351. First off is header fit, I have run two sets of headers on the P heads. First set was a set of summit shorty pacesetter headers. they fit besides a dimple that was required on the number 4 primary tube. And with a set of Ford Racing SS shortys. The ford racing headers required a shorty plug and a big *** dent in the number 3 or 4 primary tube. I cant remember. The stock valve springs in the P heads CAN NOT handle the lift of the Comp SD(Cant remember kinda drunk) cam that everybody recommends. They bind and break valve spring retainers in the exhaust side. Power was a bit better top to bottom compared to E7 heads. Low end was exceptional, bit they ran out of steam at about 4400 hundo RPM. That may have been and issue with the SD efi though. I have since moved on to AFR 165s a bit more of a roller cam and some other mods. Just be sure to have the head bolt holes reamed out to 1/2. Hell I had to do that with ONE of the AFR heads I got new in box. Still haven't sent them that dirty email. Any more questions?