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Discussion Starter #1
I'm dropping a donor motor into my 69. The engine came from a 1970 convertible with a c4. The guy I bought it from said it was a 351. Looked just like the one that was my 69, aside from the Holley Street Dominator and 4 barrel Holley that was on the one I purchased. So heres the catch. I used his block since it had only 68,000 miles and no rod knock, and used my heads because the bolts broke in his. I noticed that his head bolts are smaller than mine. So now I have a feeling its a 302, and with the c4 in there I'm almost positive. But anyway, If i am correct with the above, I should still be able to use the heads off my 351 right? What about the manifod and distributor. Thanks
 

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from a 351 to a 302, yes, you can use the heads but youll need some sleeves to put in the bolt holes to accomodate the 7/16 bolts instead of the 351s 1/2 inch ones. the intakes will not swap, nor will the distributor. most parts will change over, but not these.
 

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Steve is correct that you can use the 351w heads and the head bolt size is diffrent, but depending on years and if there 2v or 4v heads the combustion chamber size and valves are also diffrent.

Most all other parts interchangeing is a little misleading, off the top of my head these are the parts that will interchange. The heads(with the above stated) the water pump, the front cover, pulleys and some brackets, fuel pump, timing chains, cams(although the fireing order is not the same except 302 HO), valve covers, thermostat housing and that is about it.

Blocks, cranks, rods, pistons, oil pumps, dist, intakes, oil pans are not interchangable. Like I said these are all off the top of my head. mm
 

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Discussion Starter #4
Why wouldnt the oil pan fit, and also, where can I look for the serial number on this engine to make sure this is indeed a 302. But I guess the bolt size, and tranny kinda gives it away right?
 

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The oil pan wont fit because the 302 uses smaller mains and the ends of the pan are not the same. Trust me. You are correct that the head bolts give it away. If there 7/16" bolts it is a 289 or 302. With a little effort you can spot the difference right away just by a glance. Look at the with of the intakes the 302's in narrower because of the different deck heights. Also you may have problems with the exhaust fitting up to the manifolds correctly because of it.mm
 

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Also, if the new engine is a 78 or newer it could be a 351. In 78 they went to using the same heads on 302 and 351. mock it up and see if your 351 intake fits. if not then its a 302.
 

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Discussion Starter #7
Ok I just called the PO of the engine, and he told me the donor car was An H code. Do the stamp the eengine size on the intake runner or something, or I guess I could just measure how far down the piston goes as well. Well I should be able to still bolt this up right? I got the comlete engine form the guy, so really the only things I was really worried about were the exhaust manifold, engine mounts, and I guess the oilpan. Will I still be able to use the complete single exhaust system on my car, or is there more modifications to be done? Anyway, if anyones got a used 302 oil pan they dont need I'd be happy to purchase or trade some parts. The one that was on the donor was bashed up, and thrown out. Also if there is anything I am overseeing please let me know. I'm sure you have told me everything though. Thanks
 

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Discussion Starter #8
BTW this is a temporary motor while I get the original rebuilt stroked and all sorts of other good stuff. Thats why I dont want to spend that much money on the new one unless its the same engine. I mean the donor engine did come with a holley street dominator intake, and a 4 barrel holley, and sounded good. But I'd rather build up my 351 than a 302. The 351 heads bolted right up to the 302? block with no probs, and the looked like the exact same heads. I'm also going to check th pushrods and see if there is a differnce. I'll be back. Thanks
 

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H code is a 2bbl 351. hmm, the 351 is about 2 inches wider than a 302. hmm, im pretty sure that 351 is stamped in the lifter vally as well. if you are gonna yank the intake, might as well look right? other than that there are some reinforcing ribs on the back of the block between where teh bellhousing and the back of the intake are. might give it a looksy
 

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badcatt, are you sure about that? I dont think the 302's went to 1/2" bolts and I'm sure the 351 never went to 7/16". I have done a couple late 80's 302's with 7/16" head bolts. Or am I just missunderstanding you? mm
 

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Mark,
I have not taken apart a newer 351 but I have read in many publications that starting in 78 302 and 351W use the same heads./ I looked it up in "How to rebuild your Small Block Ford" by Tom Monroe. I did not find anything about the bolts but ti does state that D8OE heads are common to both engines. He does not say anything about the bolt size. I will call my buddy who has a Ford performance shop in the morning(closed mondays) and see if he knows. However if he sets the heads on the block and the 351 manifold fits we know for sure. Thanks, neal.
 

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I think you will find that in 78 they both shared the same ports and valve sizes. That dosent mean the heads are the same, chamber sizes and bold holes still would be different. I had the same book you talk about, but it got loaned out and it is still missing. mm
 

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Discussion Starter #13
Ok cool. I checked the engine, and it is indeed a 302. Now you said I could use the 351 2v heads on this block right? They are already bolted up, and torqued down using the correct procedure. Just wanted to confirm. My question now is how do I figure out what year and what car this block originally came from, cause obviuosly didnt belong to that 70 convertble. And how will these heads ultimately effect the 302's performance (Basically, What do I get when I THROW 351 HEADS ON A 302) And also will I be able to use the motor mounts, and the exhaust manifold from the 351? I guess thats pretty much it. Thanks again for all your help.
 

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Discussion Starter #14
Oh and is it possible to use heads off a 1988 ford bronco with 302 EFI? Rememeber, i dont really want to drop much money into this 302 so I want to see what I can do with the parts I already have. The money is going into the 351 stroker. Thanks
 

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you can find casting numbers by were the starter bults on. Post hhem as well as the casting numbers from the heads you removed and we should be able to get you some info.
 

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You say you already bolted the 351 heads on the 302 block? What did you do about the 7/16 bolts through the 1/2" head bolt holes? mm
 

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Discussion Starter #17
What do you mean? The bolts fit in just fine, and there are guide pins on the block. Are you saying I MUST use sleeves in the head holes to bolt them down? And if so where do I get them? Thanks. Oh and what about the heads off the bronco? Or should I just stay with the 351 heads?
 

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A 7/16 bolt in a 1/2" hole dosent fit fine to me, but I'm not saying it wont work for a beater motor for a short time. And yes I know about the guide dowls, and ritght now there all that will keep the heads from shifting. I just seen the first set of reducer sleeves a short time ago but I know Ford themselves offer a shouldered set of head bolts just for using 351 heads on a 302 block.

As far as the 88 bronco heads I dont see why they wont work, but I am not that familair with them and I know the later model heads went with a pedestall rocker setup and know you would need to use them if thats what they came with.

If your sure that that 302 is not a 70 motor you should make sure to find out that it is not newer than a 82 as they went with a 50 oz flywheel balance then and a one piece rear seal. So if its newer than 82 you cannot use your 351 flywheel.

I hope your understanding this, and why the Chevy guys always say they like there Chevys because all the parts interchange. mm
 

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Discussion Starter #19
Oh ofcourse i'm understanding. And please dont say the Cword around me...hahaha. I have to find the numbers on the engine, and when I do i'll post them, however I doubt they are newer than 82, because I think I remember the 2 piece rear main seal, I'll let you guys know. Someone also said I might have trouble with my exhaust manifod fitting correctly.; Does anyone else have any input? Thanks
 

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push rods

I did this in 1982. 351 heads on a 289.
push rods a different length. i think i used come oddball push rods, like studebaker or pontiac? i cant remember.
but they were different and it caused me to drink lots of beer
 
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