L30/M20 Crankshaft

[Bernhardt]

I’m interested to know if anyone here can tell me about the Crankshaft on a 1968 L30/M20.
When I’m reading, here and there, on other sights, more than once the big journal Forged crank comes up as being found in a 275HP 327. The articles here at C.R.G states that a 1968 L30/M20 would have the cast-iron crank 3941174. More so, I had been led to believe that the corvette 300Hp 327 (same motor?) had the forged crankshaft? As they have motors from the flint factory, I thought this might be why. But I have also read they had cast cranks in other articles??
Anyone have firsthand knowledge or a picture?
Also, the pic of a L30/M20 at C.R.G. is a 1967, and it has chrome valve cover and air cleaner. Has anyone seen that on a 67, or 68 L30. I never see that in the pictures of L30 Motors I have searched on the web? Any one have any thought or first-hand knowledge?

[Petes L48]

Not sure what picture you saw on this site, but the L30 did not get the chromed valve covers and air cleaner lid.  Did you see this CRG report yet? The illustration at the right near the bottom is of a L48, while the one at the top left is an L30 with painted valve covers.

http://www.camaros.org/l30m20.shtml

[GMAD_Van Nuys]

ChevelleWorld has information on how to identify forged and cast crankshafts by examining the parting line:

https://chevelleworld.macswebs.com/decode/crankshaft.htm

[Bernhardt]

You are right,
 I did not notice the top pic, and misread the bottom one, which was a pic of the L48.
(The RPO L48 350ci-295HP engine. A "stroked" version of the L30 327 engine.) in this item description i saw l30 and missed the rest.
I get to reading, and thinking, so hard i become blind? Thanks for the response!!
My engine has plain valve covers, with a 1tanawanda sticker? But i was second guessing if it was original, because of the pic i misread.

[Bernhardt]

Great link on crankshafts. Thanks for taking the time.
I have a few 68 forged cranks. I also have seen more than one original motor with swapped cranks, 307 for a 327 from the factory. Made me wonder more about the forged cranks. And which 327 were supposed to have them as I am getting conflicting info. As I read different articles over the years. It is already known all the 67 were forged, but I wonderd if we were sure all the 68 were cast or assumed?
This also comes from my conflict with corvette cranks, being told to different things. I have not done deep research, and most do not care, so I was curious if someone had more definitive recourse to share, than my experience?

[68L30]

L-30 0702EE Tonawanda block in a 07E 68 is cast. 

Steve

[GMAD_Van Nuys]

Here is another article on Chevrolet crankshafts that you might find interesting:

https://www.chevydiy.com/1955-1996-chevy-small-block-performance-guide-crankshafts-manual-part-2/

We used to send out crankshafts to be reground as this was before aftermarket units became available.  Today, I'd probably just buy a new crankshaft as the machine shops I used have long since closed, unless I wanted to keep the engine original.