Thread: PCV with tripower?

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I posted this in another thread but then I thought perhaps it should have it's own thread as it's a pretty specific question. What do I do if I want to run a PCV valve on a tripower setup? Take the PCV from the valve cover to the center carb base? Does anyone make a PCV carb base spacer with the PCV inlet that will fit the Rochester 2GC small base carb? I've been trying to figure this out for a while as I want to run the tripower on a 350 block which of course has no road draft tube and I don't have an intake with the vented oil filler tube.

the vac. don't have to come off of the center carb. you can pick up the vac. anywhere on the manifold. drill and tape a fuel runner if you have to.

Mike, as usual, is right on the money. If you're not running power brakes you can pull it of the existing port on the manifold, but if you are running power brakes that is not a good idea.

AHAAA! I'm not running power brakes, so I can just come off of the existing manifold vacuum port/fitting for the PCV? That would work out great. Now, I just need to find a fitting that will fit the 3/8" (?) PCV hose. Am I understanding this correctly?

Thanks for your responses.

While what's said above is true, almost all of the Rochester 2BBLs already have a tapped port in the rear of the base plate. If yours doesn't it's pretty easy to drill and tap one there.

If your carb already has the port there, any hardware store should have a selection of brass 90 degree fittings pipe thread on one end 3/8 hose nipple on the other,that will work with the limited space you have.

After looking at the Offy Tri-power I have for a SB Chevy, I don't know that I would necessarly use the factory accessory port for a PVC valve. From the location on this particular manifold it appears that only 2 cylinder would be affected by the controlled leak that the PVC causes ( 5 and 7) and I can see a potential a lean condition/hard to tune idle due to that.

Just my 2 cents.

Thanks Mike P. I got to wondering about the potential problems that you describe. It seems to make more sense to come off of the carb base if at all possible. Thanks for your input.