I have a 67 Malibu with a rebuilt 350. I would like to put the original "Chevrolet" script valve covers back on but they have no holes for breather or PVC valve. I don't want to drill them. Is there an internal breather you can put on to make this work?

Also, the motor has an old Edelbrock C3B intake. I can get a used Edelbrock Performer intake for $60. Will I see much difference swapping this out? It has 993 cylinder heads, flat top pistons, edelbrock 600CFM carb and headers.

Any help is appreciated.

Steve

Since your valve covers are unpunched, I assume you've got an oil filler tube in the intake. If not, plan on your oil changes taking a very long time (it's kind of slow pouring it down the dipstick tube). smile.gif

I'm in exactly the same situation (those valve covers are classics!) except that my engine is the original '67 283, recently rebuilt. There is a round hole in the block deck behind the distributor. (If there's one on your engine, it's probably been plugged.) A hose adapter is pressed into that, then the hose runs to the PCV valve which is screwed into the back of the carb. There is a breather (filter) cap on the oil filler tube. If your carb lacks the threaded fitting, you may have to use two pieces of hose with the valve between them. You may have to improvise - just make sure the valve points the right way.

An alternative arrangement uses an oil filler tube with a threaded boss near the top, into which the PCV valve screws. A hose connects this to the carb. Another hose takes clean air from inside the air cleaner and down into the block, again using the hole in the back of the deck. The filler tube is topped with a sealing cap (not a breather). Note that the valve in this case must be a different type from the one that screws into the carb, even if the threads and hose barb are the same size, since it flows in the opposite direction.

There are some very useful illustrations in the carb section of the 1967 Chassis Service Manual.

I hope this helps.

Reid

You can also punch a hole in the intake, right in front of the distributor for the pcv valve. Mount it vertical, just be sure to baffle it underneath. With a long funnel, you could also use this hole to add oil.

Thanks for the advice. Any takers on the intake question? I am leaning toward replacing it, but don't want to do it if little will be gained.

Thanks again.

Newer intakes are almost always better than older ones. A Performer is no doubt better than a C3B, but you would probably only notice the difference as a tenth or two on the dragstrip. I doubt you could tell the difference seat-of-the-pants.

Originally posted by Rabbit:
...There is a round hole in the block deck behind the distributor. (If there's one on your engine, it's probably been plugged.) A hose adapter is pressed into that, then the hose runs to the PCV valve which is screwed into the back of the carb. There is a breather (filter) cap on the oil filler tube...
Unless I am mistaken that hole in the block by the dist. was originally for a draft tube that ran down behind the engine and expelled crankcase gasses on the ground. I didn't know it was later converted to a PCV set-up.

The filler tube he is referring to is in the very front. Unless you've got an original manifold, it probably doesn't have a hole in it for the filler tube. If your block is a 67 it probably does, but the newer manifolds cover it. If you want to use the old valve covers you need to have both the filler tube and the rear-mounted PCV in place.

wasnt the C3B meant for a 3bbl carburetor, someone said that in one of my posts awhile back

C3B stands for carburator three barrel. Mine looks to be from about 1970-73. It is in good shape. From what I understand it was designed more for emissions than performance. Runs OK above 2,500 RPM but a little dead off the line. Thanks for all the response regarding the PVC valve.

Steve