How can you ensure a crank is a 1969 Z28 DZ302 crankshaft if the "1178" casting code has been partially drilled out supposedly during balancing of rotating assembly? Does it hurt the $$value of the crank missing the casting code?

Is there any 100% way of identifying a z28 302 crankshaft? thanks Dave

You can tell by the shape of the flange where the flywheel bolts on. I believe a 302 crank is round with a notch in it, but check me on that, because I'm not positive. The parting line should be the wide one also, since it should be a forged crank if it is an 1178.

hello, not sure what you mean, the parting line is the wide one? Also the notch,dont' all cranks have a notch out of them? can you provide more info? thanks again

Dave,
Not sure what you are trying to accomplish, but if it is a forged, 3" stroke, GM crankshaft with 2.448" main size ... there is not much else it can be but a 302 crank. If its been hacked up for balancing then its not really original any more. If you dont understand what a wide parting line is, then it would probably be best to take the crankshaft to your machine shop to have it id'd or ... post a picture here.

Bill, thanks for the info...I cannot post any picture or take it into a machine shop as it is already assembled into the short block. I am just trying not to get ripped off on supposedly a 302 short block for sale.

Dave

Dave,
It's been a while since I've seen one up close but I think there is a date code on the"1178"

For me, drilling the casting number de-values the crank.

Also if you can check, the 302 has a 3" stroke.
Good luck,
Doug

thanks Doug...I feel the same way about the value being less if it was drilled, plus I've never seen anyone drill on that portion of the crank before for balancing, usually its the other end of the shaft/"lobes", not near the journals themselves?? It just doesn't seem right to me...I will have to really look things over....thanks again Dave

Dave,
I have had to grind on some crazy places on cranks when balancing them, especially if they have been balanced once before. If it is just a short block, it should be pretty easy to take a ruler and measure how far down the piston goes into the cylinder. It should move 3" if it is a 302 and the bore should be 4".

thanks Bill...I will check it out for proper stroke etc. that is the easiest way to ensure it is a 302. As for the end of the shaft, is there also a distinct "notch" or any other way that it signifys an '1178', 302 crank?

From your experience,any idea what a 302 short block, .030 over is worth nowadays?, i.e. supposedly an early DZ block, cast 6/68, assembly date 9/68 with DZ stamping on pad, includes, std / std 1178 crank, (1178 partially missing a digit or two?), NEW :TRW 11:1 pistons, correct cam, solid lifters, bearings, timing chain, oil pump, pan & windage tray.also includes the correct z28 Alum.intake and Holley carb....basically missing the harmonic balancer, dist. & heads.

thanks again,
Dave

The 302 crank flange looks like this - no other SB crank flange looks remotely similar to this shape:

http://img.villagephotos.com/p/2002-2/13522/302CrankFlange.jpg

:beers: