sbc crank questions

Crank question. I have 2 crankshafts out of a 283 casting # is 3876768 on both cranks. Mortec website list them as forged cranks but they dont have the wide parting line I have seen on other forged cranks? Did 283 have forged cranks without the wide parting line?

 

If it has a "Wide" parting line it is forged, if it is a narrow line it is cast. Forged cranks also look a little smoother.

 

Does it have the "narrow" parting line? I've seen some forged cranks that you could not see the parting line at all.
Most 283 cranks were forged.
Larry T

 

thin line in places and no line in other places on the crank.

 

Casting IMHO.

 

that's a cast crankshaft

 

as 36-3w said, that is a cast crank!!!!

 

Thats what I was thinking but casting numbers list as forged. I was just checking.

 

Cast crank and beware it only fits later blocks >>>>.

 

Yes Cast crank. Are you trying to build something specific?

 

ALL early 283 crankshafts were forged. These must be late model 283 cranks since they are cast.

 

If you're sure you read the numbers right, it might be nice to let the guys at mortec know they have an error in their listing. mortec is a valuable resource, and making sure it's accurate is in our best interest.

 

Huh??

 

casting 847 & 768 fit 64-67 blocks only. 236 & 822 can be used in all years.

 

Just building a mild street engine. I have 2 blocks and 3 cranks. One 64 block w/ forged crank 10/10 ready to go. One 67 block w/ 2 #3876768 cranks one is fresh 10/10 ready to go. I am just trying to sort out which one I want to use. Both blocks are at the machine shop now cleaning up the holes. I was just kind of stumped with the numbers I thought the later cranks look like cast, but my casting number searches kept saying they were forged. I am probably going to use the forged crank and earlier block it had a balanced rotating ***y. and should go together the way I want. I did not know that you couldnt swap the cranks between those years. Thanks for the replies.