Thread: 428 block or 410 ?

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I have a 428 or 410 i believe just the block, it has C6ME on it and date code looks like 6A22 there is a V above the 6 and to the left also, block has 39 or 36 and 22 over 352 ON DIFFERENT PARTS OF THE BLOCK also.....I didn't see an A or C scratch anywhere, but the block looks like it has been hot tanked, and was getting ready to be put together.......Need some help with the ID,is it a 428 OR 410 or did they make another block with C6ME, measures 4 1/16 across IF I MEASURED CORRECTLY, is there another way to check the stroke and bore with no crankshaft or ? ? ? ..One more question what kind of value do these have if any....I can send pics to anyone that wants to see it, i took alot of pics...

Thanks for the help...

You want to check the cyl wall cores through the blocks freeze plugs. C6ME was a generic casting number used on many differnet bore blocks. If a 13/64" drill bit shank fits snug between the cyl wall cores the block has 428 wall cores. If a 17/64" drill bit shank fits snug it has 390 wall cores. This is known as the drill bit test and short of a sonic map a very easy way to check what wall cores were used. You can resize the 64'ths to suit your bits. It's just the standard measurement used. 6A22 is a 66/Jan22nd date code. Value would depend on which block it is. 428's are $500 and up. 390's are $100-200 for block only.

G.

Hey yas,

A 15/64TH can be pushed through barely with work, and super snug, and i mean really tight, AND won't fit in some spots etc..

Thanks Eric

Eric sounds about right for 428 wall cores. 13/64" is just a snug fit with no real effort. If you want to sell it as having 428 walls you might want to have it sonic mapped. This will tell you exactly how far the block can go and also any coreshift the walls may have that will limit overbore. From the measurement you gave it sounds like a .060 411.2, 390 bore. But my math stinks and you better double check. A tic under std 4.13 428 anyway. For the most part 428 blocks I've had went .040-.060 over 4.13 std. A sonic map runs around $60 here. Even though the C or A is not on the back hopefully it will check out and have good thickness. For sure worth looking into if selling.

G.