GT40p heads and intake?

GTp heads do not have passages for the smog pump, so if you need to hook up the plumbing to your smog system they will not accommodate it. I drilled and tapped a hole on the back of the head so I could install the smog plumbing to pass the visual inspection. I run a belt that bypasses the pump and only install the correct belt to get the car inspected.

I was able to run the aftermarket headers my car came with. (unknown brand) I had to dimple the #8 tube a little and run 90 degree plug wires. I will have to remove the drivers side header to change my plugs though. Ford Racing makes shorty headers that work on the GTp's. So, when I get around to changing the plugs I will probably buy some new headers.

If you are running a larger cam I recommend changing the valve springs.

GTp heads are basically GT 40 heads with smaller combustion chambers and of course the angled plugs.

The intakes changed after 97 and the newer ones do not have the internal EGR passage. So, to make your EGR function you will need to get a '97 or older intake. You will also have to drill and tap a hole for the IAT sensor. The '97 and older intakes have the casting for the IAT in the same place as the original 5.0 intake, the '98 and newer intakes do not.

My engine is a .030 over 5.0 with the GTp heads off of a 2000 Mountaineer. The bowls have been blended and the exhaust ports smoothed out a little and the Intakes were gasket matched, '97 Elplorer intake with the lower also port matched and "worked", B303 cam, Trickflow valve springs, 24lb injectors, 70mm Throttle body and EGR spacer, a cold air kit that puts the filter in the fender and a Mass-Flo 73mm mass air sensor calibrated for the 24lb injectors. Haven't had it dyno'd yet, but I'm guessing about 250 to 275hp.

Reg is fine.. If you are on a budget and don't have plans on spending a lot of money on engine mods this is the route to go. I bought mine on eBay for 370$ shipped to my door from Odessa cylinder head in Florida. If you buy them on eBay they don't have a core charge. At least that's how it was when I bought mine. They came with new springs and valves. All cleaned up and ready to install. Like buying a brand new set. Pretty sure they had a warranty also. If you buy from a junkyard you will have to get them cleaned up.

They changed in mid 97... so some 97's are old style and some are new style

You want to get a 96/early 97 exploder intake because it will have the internal EGR passage, a boss on the #5 cylinder runner for the ACT sensor and a boss on the rear lower for the EGR coolant return. This way you can bolt on the stock TB and spacer if you dont want to upgrade to a 65mm or 70mm TB.

Throw a set of mustang valve springs on it, no need to put on the $150 kit unless you want to.

red-fox said:

Ok great thanks! so with these heads will I need to run it on premeium feul or can I still run on Regular? Would you recomend these heads or is the effort not really worth it? I'm on a pretty tight budget and I dont really want to get anything if its not worth it.

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I like these heads. I didn't even know the difference between the GTp heads and the other Explorer GT40 heads till after I had bought the whole engine from a 2000 Mountaineer. The GT40's are also good heads and less hassle since you don't have to mess with the headers. So, if you can find either of them for a reasonable price you should get them as an inexpensive alternative to aftermarket heads. I did have to find the older intake, but am saving the newer one for another project.
I have only run mine on premium so I can't tell you if regular is okay, but it probably is.

already said.... on the Explorer and Mountaineer, up to the first half of 97

I love the GT40P's on my car! don't neglect the other stuff though. I'm sure the cam and intake that were changed at the same time had something to do with it too...
I had already done gears and exhaust, MAF, TB...

The '97 and older GT40's are good, but the GTp's bump the compression up about 1 point so in my humble opinion the p's are better.

All explorers dont have GT40p heads early 97 and older explorers actually have GT40 heads. From what I understand the GT40p heads actually flow a lil better than the GT40 does.