Quick GT40P Question

Discussion in 'Fox 5.0 Mustang Tech' started by mrswivlepants, Sep 20, 2005.

  1. I found a set of "P"s at the local junk heap for a steal. Of course I want to jump right in and toss them on but I haven't done heads before and I wanted to know what the minimum prep you guys would suggest I do to the heads before I install them. The car they came out of was a 1998 Mercury Mountaineer. I got them real cheap and they probably won't be on their long so I don't want to sink a lot of money on them.

    My other concern is the headers. I know the stockers won't work. Can I go cheap and snag up the Explorer headers as a temporary bandaid? If so, is that a stupid idea? Like I said they won't be on their long so please avoid the "IMO you should save up and get aluminum heads" posts.
  2. If they are just gonna be on there for a short time flip them over so the combustion chambers are up. Poor some solvent in them and make sure they will hold the solvent. As long as they will hold for 30min or so clean them up real good and bolt them on.

    The exploere headers will not fit.
  3. you can use stock headers, and most aftermarket shorty headers. You will most likely have to remove the drivers side header if you wnat to change plugs, but like you say, if they're not going to be on there long, it would be a waste of money to invest in "P" headers you're not going to use for a long time and that you'll lose $$ on if you sell them.
  4. I tried to use the stock headers. The passenger side worked fine but on the driver side the plug wires for cylinders 6 and 8 were against the header. Actually the boot was against the header and from what i could tell there was no angle boot or anything that could have fixed it. I just spent the $239 on headers from Jegs.
  5. the real way is to snap up the heads and let a shop go thru them... the Explore headers are real small at the ports!!

    Just me........................

  6. What's a shop going to charge?

    Just hypothetically, lets say I get a quality guy to do them...like you, how would they compare to your E7 ported heads? If they flow well enough it might be worth it to do it right. Some other posts in similar threads indicate they aren't worth porting for some reason.
  7. You'll have to bash in 2 of the PS collectors. Even then, you'll need to cut the SP boot off, bend the actual metal clip to 90 degrees and coat it with RTV. Then you still might end up firing sparks into the header. This is the sole biggest PITA with the P heads. Theyre enough of an improvement by themselves that for short term, dont bother porting them.
  8. I thought gt40 p's needed special headers?
  9. Well they do but MAC longtubes, supposedly some bbk shorties and the spec headers will all fit. Some people said they bash the collectors in to clear the plugs but I have never gotten this to work as the plugs fire into the header instead.
  10. I killed myself for 2 days breaking plugs just bought the p headers. Its the only way to go i was really thinking of screwing up my hookers but figured i would just save them for when i get different heads.
  11. I'll probably just pony up and get the "P" specific headers. Curious if they add any HP or TQ. I'd also like to see what Thumper, master of all porting, says about flow numbers compared to the E7's after a "P" port job. (no insult intended, I do really believe you are the master of all porting)
  12. When i put them on its like night and day car pulls in all rpms. i like them for what they are.
  13. You talking about the heads or the headers? I'm assuming you mean both because you were having problems with the stock headers....right? Before I do any of this I really need to do a compression test and leakdown to see how bad the old block is circa 152,000 miles. I've been on this neverending quest to get the ole' girl to pull like she did when I bought her several years ago and it just isn't happening. Next summer I plan on going with a new long block, which one is yet to be determined. In the mean time I want to mess around and see what I can do, hence the temporary home for the "P"s.
  14. So I actually got the heads today. They need a whole lot of TLC. I have another question though. I grabbed pretty much the entire valve train from the Mountaineer. The lifter, rods, RRs springs. I hear the Mountaineer 5.0 has a different cam in it though. Does that mean I can't use all that stuff? I just figured they have less miles on them so why not use them if I can.
  15. different lift.. nothing diff about it in mechanical terms.. just lift and such.. the cam is more torque related, a stock cam in a mustang is better to use.. but alll that you snagged will work
  16. Good to know. I asked because I remembered reading somewhere that certain cams require different length rods or something like that. Thanks for the info. Oh yeah, one more question, there isn't any issue with the stock valve covers is there?
  17. You can use all of the old pushrods and rockers from your Mustang engine with the new heads. I would get new lifters while you're at it as one of my 150,000 mile jewels has collapsed and makes a nasty racket at speed. You can reuse them later. The HO cam is a nice piece with the "P" heads and a set of 1.7 roller rockers wakes it up even more. The Explorer/Mountaineer's didn't come with roller rockers BTW. There are no issues with the rocker covers if you are still using the 1.6 stamped rockers. They do not clear the 1.7's without a bit of grinding. I use the stamped steel covers from a GT40 crate engine on mine, and they clear the 1.7's nicely. Trust me, she'll pull plenty hard without a rebuild as long as the compression is OK.
  18. What kind of 1/4 times do you get with your setup?
  19. good thread, and i'm curious to see what kind of times and power people are seeing.

    btw, don't use that explorer cam, its a torquey truck cam, and is worthless beyond 5k rpms or so from what I understand. be sure to re use your ho mustang cam if you're on a budget.

    as well, ditch the explorer valve springs, they won't rev either, and you stand chance of floating a valve with a decent cam. At a minimum use some good HO mustang valve springs.
  20. I guess that answers my questions on the valve springs and stock explorer camshaft!

    I wonder where I'd be able to get specs on cam for explorer etc...