The Stovebolt Site Forums The Shop Area Engine Shop Non PCV valve covers

Is there any problem with adding non-PCV valve covers to an 83 Chevy 350?

only if you don't have a vacuum port big enough to plug into .

Where do you plan to put the PCV valve? The earlier blocks had a hole beside the distributor where the road draft tube once fit, later adapted to incorporate the PCV. That setup required an intake manifold with a built-in oil fill tube with a vented cap. It's imperative that the crankcase be ventilated to prevent the buildup of pressure from blow-by gases. It needs to be done by airflow past a road draft tube and a ventilated valve cover like the pre-emission control stovebolts and V-8's, or with positive ventilation provided by the PCV valve and a clean air source from the air cleaner housing.

Bottom line- - - -if the ventilation isn't there from some source, oil will leak from every gasket and seal due to crankcase pressure buildup, and the engine will burn oil, also. The ventilation MUST be there by one method or another.
Jerry

Thats what I thought. So are you saying if I take the manifold down to a machine shop and have it drilled for the oil fill tube and top it off with a ventilated cap, I would be good to go? Or would I need to add a road draft tube? If thats the case, I'll just stick to the PCV valve covers. I was just trying to make this 350 look as old school as possible.

Thanks.
Michael

You would need both of the ports, because the one in the manifold must let the air in, and the other one vents it to the road. IMHO, I think the early 327's were the last ones with the road draft tube hole beside the distributor. It would require some serious machining to retrofit the 350 block, if it was possible at all.
Jerry

Ok, can that idea!

thanks!

As long as the engine can breathe you're fine. Chevy did not start using a PCV system until 66in CA, 68 in the other 49 states. All small journal small blocks have the boss on the back for the road draft tube, but the last year it was used was 63. 64 and 65 CA, 66 and 67 49 state cars used a tube in the front of the intake with a vented cap. 66 and 67 in CA used the same setup with a hose from the tube to the carb. I ran a similar setup on a 350 with an early intake and Corvette valve covers years ago with no problems.

Devin

Same question. I have a newer 283 that does not have the Draft tube in the rear. it use to have the oil filler and PCV in the side valve cover.

But I wanted to make it look more orignal and put on an older intake manifold and older Chevrolet script valve covers.

Now I have the oil filler tube in front with a vented cap and ran a PCV to the back of the carb but it currently gets the blowby just through a really small hole through the bolt holding the Coil bracket on. That bolt hole goes all the way thru the intake manafold. So I was hoping it would pull presurized air and blow by from the area and would work for me.

But I think that is too small of a hole.

I do not dare bore a hole through the flat spot where the draft tube should go as it is in the block not the intake manafold.

I was wondering if I should just route the PCV hose up the the oil filler tube and fasten some nipple onto the side or rear of the oil filler tube?

Would that work better of would that just suck clean air from the filler tube vent and not help clean the engine?

What is a good way to get the correct function in my current setup?

I have seen some people attach a hose to the rear end of a valve cover but they had some fancy metal work to ack as a baffle insde the valve cover and all.

My truck is an orignal V8 truck but the engine was apparently replaced with a newer 283 at some point in its past.

right I saw that one and is what I was refering to when I said "I have seen some people attach a hose to the rear end of a valve cover but they had some fancy metal work to ack as a baffle insde the valve cover and all. "

But it was done to corvete style covers that are more rigid than the Chevrolet style covers. Though that may not matter. But I have no way to fabricate something like that as it was "machined it out of aluminum". But maybe I could figure out something similar.

But I was hoping not to have to mess with the original valve covers.

Anyone have another idea?

> They drill a hole in the back of the intake where the draft tube would be large enough to put a doubled lipped o-ring in it to fit the PCV.

The draft tube is in the block not the intake. Mine does not have a draft tube there and is just a flat spot (never drilled out) as mine was a PCV in the valve cover originally.

I also use the mechanical fuel pump.

So I am still looking for a good work around. Is there any good place I could drill a whole through the rear of teh intake that would accomplish the same thing as the rear draft tube conversion to PCV?

Thanks for that URL http://www.stl-vettes.com/65Vette/rebuild-2/zz4/pcv/pcv.htm that gives me some ideas to work with.

Do you know if I chose to try to drill a hole in my existing stock cast iron intake manifold if it would be succesful?
I have never tried drilling into cast iron.

What type of drill bit would you need? Any tips on how to do it?
Or should I take it to a machine shop and have them make the hole somehow?

Or would a dremel work somehow?