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Discussion Starter #1
I have a 69 302 and a buddy said he will give me a pair of rebuilt 1979 351W heads.I"ve never done this swap and was wondering if there are any performance gains.And what problems or adapting will have to be done.Is this a worth while swap.Thanks:confused:
 

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lazycat, if those heads are from a 1979 they are most likely E5AE casting and would net you nothing over your 69 D0OE casting 302 heads. Also the 351W heads require a larger head bolt 1/2" instead of 7/16".
 

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It will run better with the '69 heads. Don't waste your time.
 

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Contributing Sr Motorhead
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lazycat, if those heads are from a 1979 they are most likely E5AE casting and would net you nothing over your 69 D0OE casting 302 heads. Also the 351W heads require a larger head bolt 1/2" instead of 7/16".
Ummmm.... E=1980s, D= 1970s. So they can't possibly be E5AE castings!

Now that we have that settled, the '79 heads would be D8OE-ABs with 69cc chambers and 1.78/1.45 valves, same castings used on 302s and 351s that year. Nothing special at all. Your '69 heads should be C8OEs with 63cc chambers also with 1.78/1.45 valves. If you were to use the bigger combustion chamber heads on your 302, you'd drop your compression from 9.0 to 8.4! Right there you're gonna lose about 10-20hp and some torque as well! That and there is the head bolt hole issue where 351Ws are drilled for 1/2" bolts, and 302s are drilled for 7/16 bolts. Many people just bolt the heads on anyway and rely upon the alignment dowels to keep things in proper place, or you can use the adapter inserts that are used with aftermarket heads.
 

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Discussion Starter #5
Well thts great saves me a bunch of work and money.If i was to find some earlier heads what would I look for or should I just go to after market heads'

Thanks So Much
 

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Even with the 69-73 351W heads you would see no improvement in performance. The early 351W heads have slightly larger intake valves and ports BUT they also have a larger combustion chamber (will lower compression ratio) and have the same extremely restrictive exhaust ports as your 302 head.

Buy a pair of aftermarket aluminum heads. Modern technology and set up with large valves, hard seats, studs and guideplates. GT40P (5.0L Explorer) heads are another alternative but require special exhaust headers.
 

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Contributing Sr Motorhead
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Just a FYI, most all aftermarket heads will be drilled for the 1/2" head bolts. I was able to find a couple of sets of decent aftermarket heads for only $400/pr used (those 5.0 Mustang guys get rid of all sorts of good parts). Both sets are cast iron - one set of TFS high ports, and the other was a set of professionally-ported World Windsor Seniors.

If you want to stick with OEM ford heads, grab a set of GT40s off a 96-97 Explorer 5.0. Or the late 97-2001 Explorer5.0 GT40Ps. Either of those are much better than your current (or any other) factory castings. The GT40s have 64cc chambers, and the GT40Ps have 59cc chambers. Either can be found in your local wrecking yards for relatively cheap (<$200) if you don't mind doing the work to get them off.
 

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Discussion Starter #8
Great info If I cant find the exploer heads I will stick with my stock heads.Thanks so much for the info
 
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