C-2 covers on a 68 327/350

[Richard D.]

Richard Wathen posted a message about using C-2 script valve covers previously, and I have a similar question.

I bought a set for my 68 327/350 (original motor) to replace some aftermarket chrome ones that were on it. The chromes had a breather cap and PCV hole in it.

The C-2 ones have a PCV valve hole, but no breather cap hole.

The manifold I got with the car did not have the front oil fill tube porvision with a breather element (I think that would have been the correct set up for the L-79).

I was told that I did not need to install a breather element (cap) with the new set up, but that does not sound right to me, especially since reading the posts on Richard's inquiry.

The C-2 covers are now installed with the PCV hook up hose going to the carb.

I've not run the car since the change.

Do I need to revert back to an original style manifold with front filler and breather cap or install a breather cap on the passanger side cover?

Thanks in advance for any advise.

Regards,

Rich

[Craig S.]

Re: C-2 covers on a 68 327/350

Rich -your assumptions are exactly right, you need a closed loop flow with inlet and outlet. FYI, the carburetor vacuum port is connected to the PCV which in the 66/67 cars is on the Oil fill tube on a side spigot. The block vent at th back of the engine goes into the air cleaner and draws any vapor into the engine to be reburned...Craig

[Joe L.]

Re: C-2 covers on a 68 327/350

Richard-----

You mention that you have a manifold with no oil filler tube. You also mention that you want to install C2 valve covers with a PCV hole, but no breather hole. If you do this, then you will have no way to add oil to the engine (unless you try to use a funnel with a small nipple and put it in through the PVC hole.

Actually, I would recommend one of 2 changes:

1) Install the oil fill tube on your manifold and use original 68 style valve covers. These valve covers have no oil filler, but they do have PCV provisions on both valve covers. The right side valve cover fitting will connect via a metal tube and hose to the air cleaner base. The left side PCV fitting will retain the PCV valve, the hose from which goes to the carb base fitting.

1968 Corvette L-79 valve covers were rather unique. They were chrome plated versions of the standard stamped steel valve covers used for 1968. These valve covers were also used on 1968 Z-28 Camaros and some 1968 Chevy IIs with L-79, but no other applications. Only one other Corvette small block ever got chrome factory valve covers. That other one was 1955 V-8. The 1968 Corvette L-79 valve covers are VERY hard to find. However, if you go out to a self-service wrecking yard and find any 1968 Chevrolet model with small block V-8, you will have the basic valve covers you need. Have these chromed and you'll have 1968 L-79 covers.

Also, adding the oil fill tube to most manifolds not so-equipped is just a matter of having the hole machined in the manifold by your local machine shop.

2) Use the 1969+ Corvette aluminum valve covers. These are still available from GM but they're a bit expensive. They're beautiful, though and much more "C3-ish" than the 63-67 aluminum covers. You can install these with exactly the same PCV connections as the 68 valve covers described above. With these valve covers, you don't need the oil filler tube---they have a built-in oil filler.

[Richard D.]

Re: C-2 covers on a 68 327/350

Thanks Guys, much appreciated.

I think I will have the filler tube hole machined into the current manifold (it's a nice polished aluminum one, and the engine seems to run real nice with it), put a breather cap at the end of the tube, and keep the cool looking C-2 covers.

I always have the old chrome ones to revert back to if needed.

Regards,

Rich