Forget all that hard stuff. Here's a super easy way to tell if it's a 351m or 400.
Open hood (if one is present) look at distributor. Look to the right of distributor at the block. Specifically the timing chain protrusion section where the distributor goes into the iron. There will be a half inch wide rectangular rib extending from the face of the block out toward the water pump. If that rib only goes half way from the block to the water pump -351m- if it goes all the way to the absolute front of the block casting -400-.
See the block on the left of
this page (one on the right is a 351clevland) that big rib indicates a 400. It'd be half as long if it was a 351m.
See, easy. An' lazy-likes-easy.
WHAT?...I mean -
what? If I'm not mistaken, the question was NOT whether the motor is a "Cleveland" or "M"! It was whether the motor was in FACT a 400(M) or a 351(M), which in the case of missing or unseen block casting numbers, can ONLY be distinguished by the crank throw. Any 351 (M) block can be retrofitted with a 400(M) crank by changing out the rotating assembly as a whole. Meaning that the crank,dampener,rods AND pistons, from a 400(M) can be transplanted into a "run of the mill" 351M block and you'll never know the difference without checking the "stroke",as mentioned earlier on in this thread. I know, because that is what I have done with my 351M!If you know how, AND have all the gadgets, swept volume can be used to determine which crank is present....on second thought,never mind! If the motor is runnin' good, why does IT matter which crank IT has? Just a question
. After all- you can't take it back to the person you bought it from and MAKE 'em eat it!
Can you?
Now...I don't know Dittliesqaut.
BUT, I think what Dittliesqaut may have been TRYIN' to say, is that the deck height of the 351M/400M blocks is "taller" than the "Cleveland" block(on the right side of the picture) so it APPEARS to have a ?protrusion? out of the block. At least I think I know Dittliesqaut.. was tryin' to say that, or at least seemed to mean that!
And, as for the poster (Andre)that made the remark that Ford made several "351's", and proceeded to try and name 'em off, WHAT?.... I mean,what?
Again, I don't recall a question being raised about the bellhousing "bolt" spacing being involved, OR even wonderin' "which" 351 he had! I'm sorry. That statement just FURTHER confuses things. His question was whether or not he could "verify" that the truth was indeed told by the person who his wife bought the truck from!! By the way,on the "Cleveland" blocks AND it's "
Modified
" versions, the 351M and 400M, the water leaves the block through the upper passenger side of the block "ITSELF", and NOT through the intake manifold -as with the "Windsor" family of motors! Just sayin',.... in case Andre ever needs to clarify the differences between a "Cleveland" based block and a "Windsor" based block in the future
! Another "By the way"-Ford saw that they had a good thing in the canted valve heads of the "Cleveland"(335) family and THAT'S why we have the "Modified" versions of this motor. Ford wanted to make the block decks taller and wider so they could more easily mate them up to the C-6 Trannys, which went behind any motor bigger than a 351, installed in the truck lines! Well...
now I'M chasin' rabbits all over the place!
Peace out! WE should always remember to NOT sweat the petty stuff- and never pet the sweaty stuff!!