PCV system

[Phil A.]

I'm installing a 350ci in my 1962 vette and need to come up with a PCV system(I think). I want to keep Corvette valve covers and leave the engine looking as stock as possible. My original thought was to use a little newer Corvette valve cover with PCV port and draw the vacuum thru the back of the stock carburetor. The stock oil filler tube would vent the engine from the front of the engine. Here's the problem: I'm using roller rockers and that doesn't allow room inside a stock valve cover for the oil separator at the PCV valve port. Should I abandon the PCV system and just vent each of the valve covers or do you guys have some clever solution?

[Timothy B.]

Re: PCV system

Phil,

Can you use the filler tube on the intake manifold for the PCV and the valve cover to vent (intake) air back to the motor. If you nix the roller rockers and use the stock baffles for both ends of the system that would be best. I would be careful which oil pump you use.

[Duke W.]

Re: PCV system

I'm using roller rockers and that doesn't allow room inside a stock valve cover for the oil separator at the PCV valve port. Should I abandon the PCV system and just vent each of the valve covers or do you guys have some clever solution?

No, get rid of the roller (tip) rockers, which are tied with K & N filters as the biggest scams ever foisted on car owners by the aftermarket.

Duke

[Phil A.]

Re: PCV system

That was what I intended to do initially, but the stock rockers, even the long slotted ones, do not allow for the lift provided by this particular cam, thus the quandary I'm in.

[Phil A.]

Re: PCV system

I think that works if the oil filler tube is capped like a "63". I would like to leave the stock filler tube if possible. Thanks

[Duke W.]

Re: PCV system

That was what I intended to do initially, but the stock rockers, even the long slotted ones, do not allow for the lift provided by this particular cam, thus the quandary I'm in.

I bet you have too much cam. It's tough to beat the OE cams. Everything from mild to almost wild, and they all use the same mild valve spring and are easy on the valve train.

You didn't say what your objective is, but the LT-1 cam with massaged heads will make close to 300 SAE corrected RWHP (close to 350 SAE net at the crank) depending on induction and exhaust system and useable power to close to 7000 in a 350 with decent low end torque and enough "attitude" at idle to tell everyone it's a highly tuned engine. A 3.75" stroke crank configuration is even better.

The best induction system is either FI or the LT-1 manifold with a 750 CFM vacuum secondary carb. The best exhaust system is 2.5" manifolds and 2.5" pipes all the way back with low restriction mufflers.

Duke

[Phil A.]

Re: PCV system

The cam is a roller cam, ground for good torque and it maxes out at 6500 rpm. I HAVE THE MANIFOLD/CARBURATOR COMBO YOU DESCRIBED, BUT IT WON'T FIT UNDER THE HOOD. (oops, caps on) Thanks

[Joe L.]

Re: PCV system

The cam is a roller cam, ground for good torque and it maxes out at 6500 rpm. I HAVE THE MANIFOLD/CARBURATOR COMBO YOU DESCRIBED, BUT IT WON'T FIT UNDER THE HOOD. (oops, caps on) Thanks

Phil-------

I highly recommend the use of hydraulic roller cams, especially in this day-and-age. Most OEM OHV applications have used hydraulic roller cams for more than 25 years now. For Corvettes it's been 30 years. However, it is possible that you have too wild of a grind. I'd recommend a roller grind that approximates the flat tappet L-46/L-82 cam.

As far as roller rockers go, there are some available that will work with the oil control baffles built into 1969+ style Corvette valve covers. The 1996 LT-4 style rockers are an example. These are an aluminum roller rocker and are not the type that I personally favor but they should work with 69+ valve covers. The LT-4 rockers were a PRODUCTION-validated piece so that should offer some measure of confidence.

As far as the manifold/carburetor situation goes, hood clearance can be a problem with the LT-1/Holley set-up. I was not aware it was a problem for C1 Corvettes but, from what you report, apparently it is. This surprises me in a way. The 1962 340HP manifold was a fairly high riser design although it did use a Carter AFB carburetor. However, it was virtually identical with the 1964 L-76 manifold which did use a Holley carburetor. So, at the worst, I would think you could use one of these manifolds with the Holley carb. Or, you might be able to use one of the 1965-67 small block cast iron manifolds for Holley carbs. I don't know of any low riser GM aluminum small block manifolds.

[Christopher R.]

Re: PCV system

I HAVE THE MANIFOLD/CARBURATOR COMBO YOU DESCRIBED, BUT IT WON'T FIT UNDER THE HOOD.

Are you sure? I don't mean to argue with you because I'm not sure. But I had a late 60's Z-28 intake manifold and an 1850 Holley carb with a drop down base open air cleaner under the hood of my '62. It was close. But it fit. The drop down base air cleaner also came from a Z-28. Not sure, but I believe the late 60's Z-28 parts were the same as the LT-1.