Technical What kind of crankshaft is this?

It was supposed to be a 401 Nailhead crankshaft but @Bangingoldtin confirmed to me that it is not. We suspect it's a Chevy crank. The dowel pin is 1/2" and the pilot diameter for the flex plate is 3.190". What say you?

 

not a small block that i know of and don't know big blocks. how about a pic of the whole crank? dz302 has a notch close to that but not rounded.

 

The flywheel register on the flange is not a SBC , or a BBC .
Looks unusual to me .

Tommy

 

this is an early Cadillac OHV crank on ebay

https://www.ebay.com/itm/264974373062

 

Looks like a Ford FE crank. Any casting numbers visible ?

 

Bingo,,,,,,Jim has it right there !
Look at the register .

And the shape of the counterweight there .

Tommy

 

I knew you would come up with a good guess. That could very well be it.

 

that number fits 49-54, or thereabouts 331

 

Bingo, Jim! Damn, you're good. It's a 331 Cadillac crankshaft.

 

It is a 53 Cad 331 crank

 

I do believe @squirrel is correct. I knew it was not a Nailhead. Now hopefully the rods are Buick and not Caddy.

 

They have Egge nailhead pistons attached to them. The guy said he had another crankshaft laying around. Hopefully, it's the 401 crank.

 

The thought "oh, what a mess" comes to mind. Good luck.

 

Good news! The seller found the correct one. I now have to drive down and swap them out. Thanks for your help, guys!