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Discussion Starter #1
My 70 XR7 has an "H" engine code (351 2v) but it has a 1970 351c 4v under the hood. Is there a way to tell the diff between a 2v block and a 4v block? Was thinking, maybe the previous owner just did a intake and head swap.

Thanks, richard
 

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He also could have just changed the manifold and carb. That is what I did to my H code. Easy and inexpensive swap. Just my 2 cents.:)
 

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Really? 4 bolt mains? Who knew?:eek2:












DON
 

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I dont think thats correct that all 4v's were 4 bolt mains but I'm not a Cleavland expert. mm
 

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Discussion Starter #6
its got the 4v heads on it too
 

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All 4v Clevelands did not have four bolt mains. However, any Cleveland can be converted to 4 bolt mains. The block is the same for 351C 2v and 351C 4v. What kind of intake is in place? Is it an aluminum intake? If so, it is most likely a 351C 2v with a conversion intake. Also, look at the corner of the heads for a "2" or "4".
 

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Discussion Starter #8
here are the numbers on the intake, it appears to be original 1970 4v. Im thinkin the previous owner did a engine swap, the more i look at it??????
 

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Discussion Starter #10
it is: DOAE-9425-L

I dont mind the 4v parts at all. I hope it is all 4v.
I have a complete 351c 2v in my parts car.
Was hoping the 351c 4v was the cars original engine. probably had a better rear end gear with the 4v pkg.
 

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Discussion Starter #11
Congrats on your seniorness jimk351c.
 

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Well, my parts book is at home, but the "D" zero stands for 1970. However, I believe it is possible for all 351C intakes to have a "D" zero for the year, as it "may" mean the year the part was originally released for production. Will have to look that up. However, that is certainly a Ford part number.

As for rear-end ratios, I've seen CJ428 cars with 3.0 open differentials, so don't count on the 4v car having a better performance ratio.

I see I've graduated to Senior status. Logan, am I now famous? Or is that infamous.... ;)
 

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The four bolt main 4V didn't come about until the open chamber headed 'Q' engine code 4V in late 71. The 70 and early 71 'M' code high compression 4V Clevelands were two bolt main blocks. I believe the block casting is slightly different on the 4-bolt blocks, since they had a unique casting number D2AE-CA.

Oh, and Bowl? Check the serial number on the drivers side rear of the block. You can read it with a mirror if the engine is still in the car. That's the only way to tell if you still have the original block.

Your engine is wearing the later 72-74 'Q' code style open chamber heads. The pimple next to the 4 you show in the picture indicates the open chamber heads. A 4 without the pimple indicates closed chamber (high compression) 4V heads.
 

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I'll buy that CJ as its at least coming from someone at least as old as the motor itself. I was pretty sure it went something like that. I always thought the 4 bolt situation was overrated. The Fords had big beafy caps and bolts unlike the Chevy smallblocks that actually needed 4 bolt mains.

I did break a 2 bolt cap one time but it was a unusal situation, the harmonic balancer exploded at about 7000 rpm and a piece lodged between the lower crank gear and chain. It pulled a tru roller chain in two and pulled #1 cap bolt out of the block along with cracking #2 and 3 caps. Broke the crank behind the first throw. In other words it made a mess of things. Short of 4 bolts and billit caps I dont think much would have helped in that situation. I have a picture someware that I should scan so everyone can get a laugh out of it. mm
 

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Jimk,

There were a bunch of different factory 4V intakes for Clevelands. The earliest is the one Bowl has. It is a cast iron square bore (Holley pattern) intake found on the 'M' code engine. The 1971 Boss 351 had an aluminum intake, also Holley pattern. Then in 72 came the low compression 'Q' code 4V engine with the spread-bore carb. In 73 and 74 the 4V intake had the passage for the EGR gasses, and the spread-bore carb was mounted to an aluminum EGR spacer plate.

I'm not trying to be a know-it-all, its just that I used to live and breathe Clevelands!
 

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Discussion Starter #18
I am out sick (and twisted) today again, i am pumped with antibiotics to kill the strep throte. i will check those numbers in a bit. I am just happy to have a 351c at all.
here is some Fast Eddie reading material
 

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Discussion Starter #19
the headers seem to be blocking the view to the numbers on the block. ill try jacking it up in a while. n' take a look from down under
 
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