The P heads do not have the holes in the back for the air injection piping.If you live in a strict smog area that will be a problem.The only other issue is the exhaust manifolds.Your stock ones will not work.You can go with explorer manifolds and a new Y pipe or aftermarket shortie headers.These heads will flow better than the e7te truck heads,but not by a significant amount.Especially if you don't make any other mods.I would compare the cost of having your heads rebuilt and ported, polished with the price of reworked P heads and go from there.A slight flow improvement may not be worth the headache.As for moding the speed density set up as long as you keep the vacuum up where the MAP sensor is happy you won't have problems.In other words don't put a radical high duration cam and you'll be ok.
Since I am not a mechanic, my knowledge is limited here. But by reading on this site, sounded like the discussion was about gt-40p heads used on later model explorers with v8. they would probably have been equipped with the 302 and fulltime 4WD. You are looking to do this with a 302 correct? I guess my only question is if they do flow better, with your stock cam and speed density, what if anything would you get out of this. Course on the flip side the site also mentioned it is possible to find these heads at a scrap yard, seeing as there have been so many Explorers in production. the yards may not know much about particular heads on an explorer v8 motor (most would not think twice is my guess), so it could net you a real cheap way to try this mod.
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