PCV question
Thread Starter
Drifting
Joined: Oct 2001
Posts: 1,550
Likes: 652
From: Richmond VA
PCV question
I have a 300HP 327 with the road draft tube and also an oil filler tube in the front of the engine with a breather cap. Can I run a hose from the road draft connection at the rear of the engine with an inline PC valve to the vaccum connection at the carb? Will this work or is it not the correct approch?
Tech Contributor
Joined: May 2005
Posts: 15,575
Likes: 118
From: Conroe Texas
If you have an AIM, take a look in the back at RPO 242. This option (required in California at the time) replaced the road draft tube with a fitting to which you connect a rubber hose. On the other end of the hose is a PCV which threads into a brass fitting, which in turn threads into another brass fitting, which finally threads into the back of the carburetor.
You can buy all of the parts you need from Paragon if you want to do it the easy way. Alternatively I understand from MikeM that the fitting that goes in place of the road draft tube was used on millions of generic 327 Chevy's back in the day, and I'm sure the brass fittings are likely available at any well stocked auto store.
Jeff
You can buy all of the parts you need from Paragon if you want to do it the easy way. Alternatively I understand from MikeM that the fitting that goes in place of the road draft tube was used on millions of generic 327 Chevy's back in the day, and I'm sure the brass fittings are likely available at any well stocked auto store.
Jeff
Instructor
Joined: Aug 2009
Posts: 155
Likes: 0
From: Tallahassee Florida
One step further from 62Jeffs post is what I did on the 327 in my '61. The hole in the back of the block is the perfect size for a standard valve cover PCV grommet. Put the grommet in the hole - push in a regular valve cover PCV valve (or a chrome one if your picky) and run a hose to the fitting on the base of the carb.
Drifting
Joined: Jul 2009
Posts: 1,610
Likes: 11
From: Tampa, FL & Harleysville, PA
One step further from 62Jeffs post is what I did on the 327 in my '61. The hole in the back of the block is the perfect size for a standard valve cover PCV grommet. Put the grommet in the hole - push in a regular valve cover PCV valve (or a chrome one if your picky) and run a hose to the fitting on the base of the carb.
rustylugnuts
Team Owner
Joined: Oct 2000
Posts: 38,897
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From: Washington Michigan
Thats a 'great' idea, but the check valve that is already incorporated in the PCV is not needed when replacing the draft tube as previously stated for using the (California ventilation system) do to the ventilation can that is present at the rear of the block underneath the intake manifold. Just run a 7/16" hose from the CVS to the rear of the carb and your done.
Drifting
Joined: Jul 2009
Posts: 1,610
Likes: 11
From: Tampa, FL & Harleysville, PA
If you make that direct connection from the vent hole in the back of the block to the carb base without either a PCV valve or the special fitting with an .090" metering orifice in it, you'll have a gigantic vacuum leak. All the can in the lifter valley does is to keep liquid oil out of the vent system - it only passes vapors.
rustylugnuts
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Does the 242 system use a breather oil cap on the filler tube or a sealed one, my 242 cal system had been Bubba'd.
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Drifting
Joined: Jul 2009
Posts: 1,610
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From: Tampa, FL & Harleysville, PA
rustylugnuts
