How do I tell if my 283 crank is forged or cast?

millis

Not to worry, all 283 cranks were forged.

I wondered if that was the case. Thanks.

millis

Not all 283 cranks were forged. Some late cranks were cast, I have one.
It was in a 1967 engine. Check the parting line Narrow is cast wide is forged.

Let's put it this way, almost ALL 283 cranks are forged and to me a cast one will be very rare indeed!

And don't forget that the early 265 and '67, Z-28, 302 engines uses the same 3.00" stroke SJ crank.

pdq67

Yes, ~10 years of 283's saw forged crank, but starting in 1964 they were also cast in the lo-perf motors (mostly in Nova's, base model Chevelles, and such) by the end of the 283 in 67 more were cast than forged. In fact, the 283 cast crank is the only one I have ever seen where GM used the same number for both cast and forged. One that can be either is the number 3. something,something...6764. I remember that because it's the same years that it was available (64 - 67 only backwards)
So pdq is right, finding a cast 283 crank was rare. But 'these days' finding a 283 crank at all is getting pretty rare. And of those that survive it is only common sense that the later years (late 60's) are are going to be the more common. In that it's a crap shoot.

Like blue said, the parting line is the tale-tale indicator, but if in doubt, have your machinist check it.

Just curious...Is there any interest in a 283 shortblock?

I've got one that came in a Camaro we bought years ago and had a set of 461 heads on it with a Torker intake and nice solid cam. It was nothing for low end torque but it sure would scream in the upper RPM!

It was a geared wrong for a street car so we changed out the cam for a mild hydraulic with Rhodes lifters and replaced the intake with a regular performer to try and get it more streetable. It lasted many years until we started to tear down the car and build a "correct" engine. Now it's just sitting and I'd rather see someone get it who could use it...

What the heck is a parting line and where is it on the crank?

millis

Read here:
http://www.nastyz28.com/sbcmenu.html

FWIW I have a cast 283 crankshaft in the garage, it's a 1967.

Here's a visual aid for the casting lines:

http://i4.photobucket.com/albums/y120/dwright406/crankcast.jpg

http://i4.photobucket.com/albums/y120/dwright406/crankforged.jpg

Thanks!

dw,

Those are good pic's!!

THX!!

pdq67

i just tore a motor apart the other night from a 65 chevelle that had the cast crank... first cast 283 crank ive ever seen.

Me too, I am a winner! I found this number on my crank:
GM 4-3849874

According to the link with the numbers mine is cast. *tear* I guess I wasted that $100 so long ago for my first ebay buy. Guess I need a different crank for my high RPM 302...

millis

if you want a 283 block you can just get a 307, i think that 307's were a 283 block with a 350 crank.... im 90% sure. i dont think that your crank would be good for a 302. i have a forged 283 crank just like yours. i was going to build a 302 until i actaully found it at work and realized it was a small journal crank. iv been told that small journal cranks arent very good for 302's (correct me if im wrong) 67-68 camaros had small journal cranks in their 302's and the 69 i belive had a large journal crank.

I wouldn't say that b/c the '67, Z-28 used a SJ forged crank fine!! Little-bitty rod bolts and all...

And I beat on my old junk301 alot of the time above 7,000 rpm, up to when my points would bounce, like at 7,500 rpm!!

It had a '55, 265 crank in it w/ who know's what 283 rods b/c I was afraid to use the skinny 265 rods in her!! Unbalanced and w/ a used junk motor Duntov solid lifter cam that I coffee-canned the lifters and she still ran great to me!!

I love these little engines!!

I'm gathering parts for another!! But this time, I'm shifting her above 8,000 rpm for the fun of it!!

Show the ricer "pup's" what a little-bitty, short-stroke, Chevy 301 V-8 will do up top!!

I'm guessing 425hp at 7,000 is all, a mild motor...

pdq67

A 307 is a quarter inch stroked 283....uses a 327 crank with 283 bore. They are a pretty good motor when you rebuild them.

Ditto if you want a little engine w/ more grunt is all STOCK-LIKE!!

pdq67