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i have a 97 f150 4X4 with a 4.6 with 50 thousand miles on it. unfrotunately it has blown the head gasket on the passenger side and is leaking oil onto the exhaust. I heard that these paticular heads are prone to this type of blow out. what are my options. ford wants $2100 to do both gaskets, but what is the chances it won't happen again. for $2100 is there other heads i could upgrade to that would substantially improve power. perhaps off a mustang or a mark VIII. will these heads bolt on, will the intake match up or will the mustang/lincoln intake need to be used and finally will the computer function properly. how about aftermarket heads. i've looked around, but so far all i can find is mustang heads. will these mustang heads work or do they require modification. If i'm going to spend $2100 on engine work i want some performance and not headgaskets that will end up leaking again. thanks
If you want to replace both heads I would go with the updated PI heads. Course if you do that you will need the intake too. Plus I think Comp makes a new cam for these heads that you can throw in. Not sure how much you want to spend on this. Check out this link for the heads - http://www.performanceparts.ford.com...tKeyField=6124 These are preassembled with mustang GT valve train and cams, not sure if this is similar to truck engine. There is another site where I found the head without the cam and valve train installed but I can't remember where. Might want to call and see if this will work if you plan to order.
The PI heads came out in 99 or 2000. Can't remember which. If I remember correct you get between 20 and 25 horses. Maybe more. You probably have the Romeo heads (named after the plant they were produced at).
Here is what I recommend for your 97. Assuming you can do the work yourself, you can do the job rather reasonably.
Get your non-PI heads fully ported, with a five angle valve job. Two shops that do excellent work off the top of my head are fox-lake and Renegade Racing.
Have them install PI cams into your non PI heads.
Install a PI intake on your new ported non-PI heads.
With this combo you will make more power than ported PI heads, and you will retain the stock compression level.
If you put PI heads on a NPI motor, then you will bump your compression level up.
It is very possible to make 300hp at the wheels N/A with a 4.6 mod motor. The combo I have seen make 300+ HP was a built shortblock, fully ported SVO heads, with a ported and port matched Bullitt intake, and custom ground cams.
The PI heads are the same on a truck and Mustang. Same valves, cams ETC. HotRod mag put a 5.4L in a 99 GT out of a van awhile back and checked the heads. They were identical.
Non-PI heads are probably the same way.
this i am not totally sure about, but i think the pi heads are only for the 5.4l . i would just replace the head gasket on the passenger side and not worry about the other. the reason is the passenger side oil feed is and the back of the head and when it leaks it runs down the head to block matiing surface and drips directly of the rear of the exhaust manifold. the left head (or drivers) has it's feed galley at the front of the head, behind the front timing chain cover where it never creates a problem leaking externally. NOW do these leaks every get bad enough to creat oil problems??? i have never seen one go past a annoying smell. i would not waste the time of money doing the left headgasket, unless u want to try some performance ideas. ford has inproved their headgaskets for these modular engines, USE FORD HEADGASKETS!!!)
thats why at the beginning of my post it says, " this i am not totally sure". the only time i have run into a pi head was working on a 5.4l there was a tsb about not swopping pi heads for non pi heads, that was the first i had heard there being any difference.
okay help me out and tell me if this is going to work or if i'm better off with the other ideas mentioned above. I have found a set of Mark VIII 4.6 32 valve heads new and complete for $495. If i were to use these heads who much would it raise the compression and what would i all need, would i need a different intake, timing chain cover ect. And how about the computer. will it still function properly or would need to be changed too.
Justin H, do know an approximate cost to do such modifications to my non pi heads or possibly a site address where i could find this out.
Thanks alot for everyones input, with out you guys i might end up with something that won't work.
New wiring harness would be required too anlong with a proper PCM, etc!!! You would need a PCM that is compatible with your vehicle and the modified engine.
Possibly one from a 32V Navigator might work. Not sure though.
good luck putting 32 valve heads in place of 16 valve heads, different chain, maybe different front cover, different timming chain guides and tensioners, i would say different intake, change pcm. if those are good heads though they seem cheap, may want to buy them and put them on ebay. a new 4.6 head has got to run double that with out valves. good luck with your project
Okay, the 32 valve heads seem out of the question as i don't want to change that many components. looks like i'm going to stay with the old heads if i can get them to seal properly.
Psolver do know of the part # for the updated ford gasket and for the old gasket. I talked to the parts guy at the local ford dealer and he hasn't clue what i'm talking about.
justinH, will the PI intake directly interchange with my old intake or will other stuff need to be changed too.