Although expensive, that Wagner adjustable PCV valve is an interesting solution. I expect that they don't sell enough to allow for huge profits. I think that it is a clever idea and would not blame a person for investing in one. The performance-enhanced daily driver might actually benefit from using this. It would allow one to actually control the flow and mitigate unintended vacuum loss due to an unfortunate PCV choice for a given engine carb and cam arrangement. If you did go this route, you might want to also get a rebuild kit while it's available.

And, yes, a properly-engineered PCV valve will keep the crankcase and oil cleaner. Even more effectively than a road draft tube. A poorly-engineered PCV valve choice will possibly cause either poor crankcase scavenging, or, excessive vacuum loss that can lead to idle and/or off-idle issues.

I'm not going to change mine as it looks original and the car doesn't do many miles each year, so if I have to change oil a little more often it is no bid deal for me. I still want to ask the question to you guys that have done the conversion, did you notice a definite change in the cleanliness of your oil?

IAN, YES.

Frank/Rebop

Bristol, In ( by Elkhart) 

Any insight on connecting the vacuum end of the pcv onto the same vacuum line feeding my vacuum wiper setup?

I'd probably put a check valve on the wiper line anyway. You absolutely do not want ethanol fumes to find their way to the vacuum wipers. Nor to brakes for that matter. Check valves help to keep condensing vapors from destroying things that are less than compatable with today's fuels.

Sorry in advance for the newbie questions. It was suggested to me that the draft tube could be vented via a bung, welded into my exhaust pipe, near the manifold, since it was a pre smog vehicle.

This would help with the vacuum. Is this viable? would the exhaust gases be hot enough to burn off the vapors? Legal? If so would using the pcv be advised?

John

Unibody...What you describe is a drag racing idea to evacuate the engine to run in a vacuum for "free". You see it used a lot where racers do not want to install a true vacuum pump costing the extra HP. You need to install a A.I.R. oneway valve in the system to prevent exhaust gases from entering the engine. I had one on for years prior to the pump. I have never heard of anyone using one on a street engine.

A PVC system is for emissions which actually helps your engine compartment clean and can help with engine leaks also. I installed aftermarket ones in the 60's in when California mandated them. No matter the car brand an AC unit worked the best. We ruined a lot of valve covers and air cleaners with putting holes in them. You always needed to turn out the idle mixture screws sometimes a lot depending on the condition of the engine.

56 Vic, B'Ville 200 MPH Club Member, So Cal.

What I understand is that the race system does not function at low (street) engine speeds. So it will do nothing for you.


Lawrenceville, GA

Charlie..I agree you need a lot of exhaust flow to make that style of pan-a-vac system work. That why it was only used in racing and the tube welded in the exhaust header had to be done correctly. The belt driven vacuum pump system worked all the way thru the RPM range. There are still skeptics on it's use but I'm not one of them....JD

56 Vic, B'Ville 200 MPH Club Member, So Cal.

Fair enough, thanks for the responses.

Now would a pcv valve correctly placed in the valley pan down draft tube location be superior, or would this set up work better coming off the valve cover? I ask because i have both a modern down draft tube adapter, a down draft tube, and a hole in one of my valve covers. I could even y a combo of both if called for. I plan on making my 61 unibody truck my daily driver, and would like it to run as clean as possible crank wise.