540 crank internal or external balanced ?.
 

https://cimg7.ibsrv.net/gimg/www.off...10105e5822.jpg
https://cimg1.ibsrv.net/gimg/www.off...cd5ddf9099.jpg
https://cimg6.ibsrv.net/gimg/www.off...ab9a764bd1.jpg
Anybody recognize stamping, manufacture.
https://cimg3.ibsrv.net/gimg/www.off...1add5141a4.jpg

I purchased engine with no specs. 4.250 stroke forged crank. Is the S for Scat?. Logo below S, I don't recognize.
https://cimg4.ibsrv.net/gimg/www.off...1c42f8dd86.jpg

Looks cast to me.
Pretty sure you can get a cast steel 4.25” external balances crank, so be careful.

After measuring main journals it needs to be cut a few.
since it's cast steel I will locate forged crank to use.

Is there a number on the front of the front counterweight ? That is where most aftermarket cranks are numbered. If the crank is standing on end you should be able to look down at it and see it.

That almost looks like a stock GM crank. Are you sure it is 4.250 stroke ? Somebody made a mess out of it drilling all of those holes.

I just found a Callies forged crank.
I'm good now.
I'm not using this cast iron crankshaft.