Messages

1

Restoration / Re: Smog tubes for SBC with A/C

« on: January 29, 2025, 11:55:54 PM »

The exhaust manifolds were unchanged between the three engines: base 327, L30 327, or L48 350. The manifold design was the rear-exiting "log"-type. The exhaust casting numbers for 1967 were 3892679/3893608 (LH/RH w/o A.I.R.) or 3892683/3872730 (LH/RH w/ A.I.R.). In 1968, the Air Injection Reactor (A.I.R.) emission control system (a.k.a. "smog") became mandatory for all manual transmission cars; the exhaust manifolds used in 1968 were therefore the same as the 1967 A.I.R. version: 3892683/3872730 (LH/RH).

The 1968 L30 and L48 A.I.R. pumps were identical, installing differently than the smog pump on the base V-8.
taken from CRG

2

Restoration / Re: L30/M20 Crankshaft

« on: January 29, 2025, 11:45:08 PM »

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?

3

Restoration / Re: L30/M20 Crankshaft

« on: January 29, 2025, 10:54:04 PM »

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.

4

Restoration / L30/M20 Crankshaft

« on: January 29, 2025, 01:23:38 AM »

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?