Fox Blown Head Gasket-upgrade Ideas

Oh, I don't know about that. I've got a set of GT40X's on my 331 and am quite happy with them. Car pulls strong all the way to red line and the heads are about as direct bolt on as you're going to get. Not the performers that the Trick Flows or AFR's are, but still comparable...and still a step above the GT40/ GT40p's.

And don't be fooled, refurbishing a set of GT40/GT40P's can break the bank in a hurry. When all was said and done, my GT40X's only cost me about $200 more than a set of GT40 iron heads after the necessary machine work and valve spring upgrade.

Also, the pedestal mounted rocker arms only become an issue at sustained high RPM. The stock ECU cuts fuel at 6,250RPM anyway, so it's really a non issue for 95% of owners.

Comparative AFR's and Trick Flows will make slightly more power, but if you've got to buy stud mounted rockers, or longer pushrods, they can end up being a fair bit more expensive. If you've already got the pedestal mounted roller rockers and can find a set of GT40X heads for a good buy, they're well worth the investment.

Well said, I think those are great points also :nice: money into them is the key.
 
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No trick question. My bad. I guess I skipped right over you said GT40X... And I even quoted you!! :bang:

I have been tearing my car apart and finding a butt load of little crap that needed to be fixed for 2 days straight. It's been keeping me up nights thinking about what I need to do and how much friggin money it's costing me. Brain malfunctioning...

Someone please :uzi: me...
 
The bloody knuckles and sleepless nights will be worth it in the end, the first time it sparks to life. Be patient man, we have all had to endure the frustration at some point.....and some of us just keep coming back for more!!!
 
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What brand/kind of heads are we talking about here?

They're Ford heads. You see them on their crate motors and I think they can still be had from their catalog (not 100% sure about that). GB is right though, they are pretty nice heads for the money and I wouldn't mind getting my hands on a set if the price were right.
 
The bloody knuckles and sleepless nights will be worth it in the end, the first time it sparks to life. Be patient man, we have all had to endure the frustration at some point.....and some of us just keep coming back for more!!!
Its all about highs and lows.. For me the highs are high and the lows are low. There really isn't a middle ground. I have plenty of sleepless nights fwiw.
 
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You can just replace the heads if you wish, but the amount of additional power you make will be determined by the supporting parts involved.

Heads alone probably won't net you more than about 20-30hp without a good intake and other induction components to back them up. This goes for any aftermarket cylinder head.
 
I'm going to strongly recommend you at the very least pick yourself up an Explorer intake for the swap (get one off of a '96 as it still has the correct EGR passages). The other items you listed can be pulled on and off with minimal fuss, but the intake as you now know is quite involved and makes a real mess. They can be had for around $100 in most cases are a big improvement over your current stock intake. Heck, the cost of replacing the intake gaskets a second time is half the cost of the heads. It'll cost you more money and effort not to run them.....DO IT!!!

You can find one in your area, or nearby with this http://car-part.com/

Also, make sure to get the M-9439-A50 intake gasket kit, or the Fel-pro equivalent. The GT40X's have the intake ports located slightly higher than most and a set of standard 1250 intake gaskets won't cut it. Also, didtch the corked ends that come with the gasket kit and use "The Right Stuff" sealant. Lay it on thick and you'll never have to worry about a leak with it.
 
excellent info thank you. If my heads end up ok and not cracked or damaged I'm keeping them for now. Would it still be wise to upgrade to the explorer intake with stock heads?
Since you've already got the intake off, sure....every little bit helps. You might pick up another 10hp or so in the upper regions. Probably not much in the SOTP feeling, but noticeable. It's really up to you.

Going one mod at a time generally doesn't produce large increases in power. You're not going to feel 10hp that an intake will give you like you will the 75hp a H/C/I set up will. I've always found it best to do them as a consorted effort to get that big "hit" we all love, but it's up to you.
 
I wouldnt waste the time and effort to simply swap intakes. At best you are talking about 10-20hp. Wait untill you do the heads and do it all at once. The explorer intakes do not come with the #5 intake runner tapped for the IAT or the passenger rear boss tapped for the coolant line. No big deal- just start off with small drills and work your way up and then tap them. If you pull the explorer hard coolant line you won't need to tap the lower rear intake as the coolant tube attaches to it, vs on the mustang it goes into the intake. Most guys end up just capping off the EGR coolant lines anyway.

Get a 93-96 upper and lower, as they have the hole in the middle of the intake for the EGR.
 
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I may wait like you mention mike. I would like to get the car back up and running sooner than later. I would need to do some serious research to figure out all the tools and methods on these explorer intakes. And not to mention research methods on drilling and tapping properly. I have tapped existing stripped threads before but never drilled and tapped new holes. I don't quite know how all the intake/vacume/egr/water lines work either just yet. I need a diagram/white paper to explain it all. Or at least research threads and sites on it. Without understanding the flow of things I wouldn't want to start drilling and tapping and get it wrong.

Basically the heads will take me a while. I'm a do it yourselfer, not a professional. Gonna take me a bit to figure it all out ;-)

Gearbanger thanks for all your help, Mike you as well, I think I have made my decision to stay with stock for now(unless the heads end up cracked...). If they end up cracked I will return here for help maybe finding documentation on the methods and diagrams for the intake swap.

Tom