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Yes they will fit but there are alot of things to consider here. One I think that the bolt sizes are different. You need to check into that. It won't stop you. They sell special bolts or inserts or something to make it work. Just call places that sell heads and they can tell you. Next, you need to know what size combustion chamber these 302 heads have. You don't want to lower your compresion too much or raise it too much. I don't know why you don't just get some 351 heads from PAW or something like that so you don't have to worry about this. If you already have some 302 heads then they can be made to work.

Austin
 

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You have to drill out all the head bolt holes in a 302 head to bolt it on a 351. 302's used 7/16" head bolts while 351's used 1/2" head bolts. They make special sholdered bolts to put 351 heads on 302's. Most 302 heads are worse than 351's when it comes to port and valve sizes and had smaller combustion chambers as well. Do yourself a favor like dablack said and find some 351's. mm
 

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or was it car craft???...

Hot Rod used a set of GT-40 P heads on a 351 a while back. they are off of the late model 5L Explorers and such. theres a place that sells them complete for less than 700 or so. on a worn 351 they were able to pull around 335 hp. that was with a mild cam and a Performer RPM intake. it was one of the Junkyard Jewels stories. might be worth checking out.
 

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Hey sixt9, He already has a set of DOOE 351 heads. What do a set of gt 40's run even at the junk yard? Spend the same on his set of DOOEs and your better off. Truth is all sb ford heads suck, especially on anything bigger than a 302. The 69-70 351 heads were about the best you can get for a 351, not counting Ford motorsports or aftermarket. mm
 

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I've been running world products seniors (they were called Dart ll's when I bought them) on wvcat for about 10 years and have never had the valve cover off. One thing you have to look at is chamber size, mine have 2.02/1.60 valves and 64cc chambers, I think the stack heads had 58cc(not sure) but I put .150 high tops in which bring me up to just over 10:1 compression. By the way I can run regular unleaded with no ping due to the chamber design(heart shaped) An added bonus is screw in studs and guide plates are included with the assembled heads. When I bought them I was in the same situation, mine needed rebuilt and once you figure the cost it isn't that much more for the world products heads.
John
 

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oh yeah, basically all SBF heads errrr.. suck. but the 69 and 70 ones are the best. still, considering that the best castings have only a 1.84 intake valve and thats considered big for stock.... thats pretty sad. the 59cc chamber is pretty cool though
 

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Don't count the GT40p out. Check out the next couple of issues of Hot Rod. They had a bad ring seal in the junkyard jewel 351 and wasn't getting good compression. Once they fixed the rings they were getting 380 HP. The cambers are so efficient that you can turn the timing down w/ out the loss power. They flow way better than 69 351 heads. I'm keepin' my eyes open in the JY for a rolled over V8 explorer.

Austin
 

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I dont go along with the GT40 route. Especailly you telling how they flow WAY better. Who was doing the flow test? They can be manipulated to produce desired results. The early W heads when done properly will do rather well. Anyway my point is how much will a set of GT40p's cost ? I asked that question before and nobody answered.

My hunch is it is not going to be an inexpensive way to go. First off I have not seen many junkyards that will rip a set of heads off an engine just to sell the heads. I can't find any decent buys in the junkyards anymore anyway.

The fellow asking about the heads gives the impression he is not unlimited in funds and dosen't care that much about power anyway. He was wanting to know if he can use what he has.

I go along with WV Cat that if money is going to be spent then the World Product (Darts) is the most effeciant way to spend that money. Just bolt em on and go!! They will also leave any GT40's (at very little more money)in the dust. And if you want to go fast later they have all kinds of room to grow.

You guys need to take your magazines with a grain of salt. Things get slanted in there. mm
 

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I see what you are saying ModMark. I do. If I wasn't so lazy I would have explained my stance better. First let me introduce myself so you know where I am coming from. Number one, I am a car guy, number two, I'm a mechanical engineer working for NASA down here in Houston. I bleed ford blue. Also, I was backing up the GT40p heads not because this guy should get them but just for the list's info. I think the guy should get some 351 heads from PAW like I stated before. Now about the GT40p. There are several things to consider in a cyclinder head. One is area under the curve. Two is price (availability). Three is efficiency. The GT40p has 59cc combustion chambers, great for keeping your compression where it should be. It will also flow better than a 69 351 head in the intake and exhaust at all points of lift, from .100" all the way to .500". If you want to talk area under the curve then the GT40p kill's the 69 351. It also has a intake to exhaust ratio of 70% which is great for the stock to 1/2 race cams most of us run. Now for the bad stuff. These heads are so effiecient because they have a revised chamber design. The spark plug is in a different spot and angle. That means special headers so you can still change the plugs. Several companies are already suppling these heads. Central Coast Mustang is selling tri-ys for us the in the classic cars. Price? You can get them from Kar Kraft Engineering for $479 a pair. The springs are the ones from ford and are good to 0.530" of lift. Or you could be really cool and get them from CCM for $639 w stainless steel valves, gprings good to 0.600" and they will even drill them out to be mounted on a 351! That is why I like the GT40ps. Just wanted you to know that I don't just through stuff out there w/ out really thinking about it first. But then again I could be wrong so take it w/ a grain of salt.

Austin
 

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Now I appreciated that reply. Just so I can give some back ground on myself also, I have raced Ford stock cars for almost 2 decades and have actually spent money on the things I have learned. I agree with what you are saying on the GT40's to a point considering you have explained the price situation. But I disagree about the 59cc chambers for the 351. The 69 351 compression can get pretty high with that small of a chamber, especially with flat tops instead of the stock dish pistons. ( I'm talking for a mild street engine) Can the stock valve train be used with the GT40's? Lets see the price differance, $639 for GT40's or $750 for World products? I used your higher price with the ss valves because thats the way the WP's come. The choice is easy for me. mm
 

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I had no idea that the WPs were that cheap! You are right that it is a tough decision. I was just defending ford stock heads. You have to admit, not bad for an explorer casting. Oh yeah, if you want to build your own, you can get bare castings for $110 each.

Austin
 

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Yeah there listed for $795 in Summit but I can beat that locally and I have seen Summit beaten by other places also. mm
 
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