Need some schooling on 351 Cleveland ID

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moparbrian

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I have 2 Cleveland motors near me for sale. Both are marked D2AE-CA. One seller swears it is a cobra jet engine. The other seller states it is just a 351 Cleveland no CJ.

I am now confused as my book states the D2AE-CA is a CJ motor.

Please help my confusion and school me about this.

Thank you
 
They both may be correct. The D2AE-CA was used in both 2-bolt and 4-bolt (CobraJet) configurations. The only way to be sure is to check whether or not the blocks are 2- or 4-bolt blocks. Are the engines complete, or just the blocks? If they are complete the CobraJet engines will also have the spreadbore carburetor and intake manifold.
 
In that case my guess is that they are both 2-bolt blocks, and neither are CJ. Tell the guy that says it's a CJ engine to prove it by taking off the oil pan so you can see the 4-bolt main bearing caps. It's possible someone degraded the engine, trying to make it more economical. It's also possible that a 4-bolt block found its way into a 2V engine at the factory.
 
As Don said, Ford used the same D2 blocks for either 2 or 4 bolt mains. I've read a lot of interesting posts (on the Clevelands Forever page) on the 4 bolt blocks...some say the main webs are actually weaker on a 4 bolt block due to the reduced section area (from the tapped outer holes). I'd have to, at least, see engineering cross section, and likely run a finite element simulation before I could decide for myself. Just passing on the info.

That being said, unless there's a specific reason you want/need a 4 bolt, I'd be more concerned with the cylinder bore size. .030 over should be considered the limit of overbore for the D2 block and even that can be sketchy.
 
some say the main webs are actually weaker on a 4 bolt block due to the reduced section area (from the tapped outer holes
This sounds like something the guy without a 4-bolt main block would say!

As others have said, D2AE-CA is the block casting number, the same block casting could be finish machined as either a 2 bolt or 4 bolt version, so there is no way to know which externally. You could make a semi-educated guess by comparing the block data code to the head(s) date code- if they are close then probably the 2V heads are original and its a 2-bolt block.

If you are just shopping for a core, I would be more concerned about what the bore size was (virgin vs. already oversize) as I would prefer the candidate with the most 'meat' left in it. The 4-bolt mains *might* be a benefit if you are abusing the engine with a lot (7k+) of RPM. Otherwise you are just paying extra...
 
+1 on what milan said about the bore. The 4 bolt mains are more of a bragging rights thing for most applications. Chuck
 
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