LSx PCV and Norris catch can

[parsonsj]

I just got back from my test drive after removing my hot rod billet valve covers, racing PCV, and K&N breather on II Much (427 LS2). I replaced all that with factory valve covers, factory PCV, and a Norris catch can. I plumbed the passenger valve cover to pull in fresh filtered air from the engine air cleaner through a one-way check valve so oil doesn't go the other way into the engine.

The old setup dumped a lot of oil into the intake tract (the car would blow smoke during decel... particularly on the track). The old PCV setup was sitting right on top of the #7 exhaust rocker arm, so it was getting a lot if oil mist, with no baffling.



The factory setup is fully baffled, with holes drilled between the rocker arms to reduce oil mist.

Anyway, I couldn't be more pleased. I can feel vacuum at the intake port to the PCV system inside the air cleaner, and the catch can was absolutely clean. I even think the factory covers look better, but maybe I'm just excited to have fixed a problem.

Anyway, here's another nod to factory parts for street use. Those engineers at GM do know a thing or two.

jp

[oestek]

How about some pics, John?

Thanks!

- KO

[CarlC]

I hear ya John. I too am going with a lot of OE derived parts.

Case in point, I'm going to use the Mann-Hummel Provent 200 catch can. Pics and descriptions here http://www.emotors.ca/articles/128.aspx I don't exactly did the guy's hose type, elbows, etc.

The Mann-Hummel homepage is not working for some reason today, but they have a good description as well.

It's a very nicely designed part. Very OE in appearance and functionality. I've buffed off the barb on the inlet/outlet and made delrin bungs that will epoxy in place. A steel tube with a rolled bead on the end will press into the delrin bung an allow slip-fit hose attachment.

It has a return line that can be plumbed into the oil pan. If below the oil level then no check valve is needed.

[andrewb70]

The valley cover on my L92 doesn't even have a breather tube.

Andrew

[parsonsj]

Andrew, do your valve covers have an inlet port on one side and a PCV on the other?

Kevin, sorry. I'll get some pix up.

jp

[andrewb70]

Andrew, do your valve covers have an inlet port on one side and a PCV on the other?

Kevin, sorry. I'll get some pix up.

jp

The driver's side valve cover has a nipple, as does the passenger side. Neither are hooked up at the moment. So is the driver's side an inlet?

Andrew

[parsonsj]

And Carl, that's one cool setup with the German kit. Sweat some AN fittings and go for it. Post some photos of how it turns out.

It has a return line that can be plumbed into the oil pan. If below the oil level then no check valve is needed.

Wow, what a great idea. I wonder if I could do that. No drainage necessary. I'd need a check valve though.

jp

[parsonsj]

One is a fresh air inlet, and the other should go to a PCV and on to the intake manifold.

The idea is to allow clean air into the crankcase to allow crankcase vapors to be evacuated via engine vacuum. I've been told the PCV setups are one of the main reason for increased engine life in later model cars.

jp

[andrewb70]

So does the driver's side air inlet need filtered air?

Andrew

[parsonsj]

On mine, the passenger side is the inlet. You'll need to pull the covers to be sure which is which. And yes, you should use filtered air.

jp

[andrewb70]

On mine, the passenger side is the inlet. You'll need to pull the covers to be sure which is which. And yes, you should use filtered air.

jp

How do you tell?

Andrew

[parsonsj]

The inlet is a double plastic baffle, all contained in a 1" vertical mount inside the valve cover. The outlet is a long horizontal baffle that goes most of the length of the inside of the valve cover.

Perhaps you ended up with two inlets??

jp

[andrewb70]

The inlet is a double plastic baffle, all contained in a 1" vertical mount inside the valve cover. The outlet is a long horizontal baffle that goes most of the length of the inside of the valve cover.

Perhaps you ended up with two inlets??

jp

I remember what you are describing. My driver's side is the intake and the other one is the vent.

Andrew

[tom_a]

I think I also will go back to factory covers. I went and looked in the garage at my OE covers. John I am still not sure which is outlet etc. I may be confused, but if you look at picture both the PS and DS rocker covers have baffles?

Here is top which I believe is similar to what Andrew was explaining.

Also, my engine does have the fitting in valley cover. Not the best shot but you get the idea.

Not meaning to hi jack this thread just trying to understand before I go and buy one of these catch cans

Thanks,

[andrewb70]

My valve covers are just like Toms.

Andrew

[CarlC]

Mann-Hummell has a check valve available. It's something like $15 through one of the Porsche sites. My friend and I both bought the same setups and paid $150 including shipping for each complete setup.

No joy on sweating on AN stuff. It's oddball diameter due to metric sizing, and it's all plastic so trying to attach anything that will apply torque will likely not hold up well. The thing is super light.

[parsonsj]

Andrew, you and Tom have "LS6" style valve covers. The PCV outlet is designed to go from the valley cover. The fresh air inlet is the nipple on the cover with the fill port. Leave what is the old PCV port on the other valve cover alone... and use your valley cover instead.

Legend on LS1Tech has it that the LS6 style is better at keeping oil in the engine, but most of the hardcore racers use a catch can anyway.

jp

[andrewb70]

My valley cover doesn't have a PCV hose, like Tom's engine does. Tom has an LS3, mine started life as the L92 truck engine.

Andrew

[parsonsj]

uh... I dunno. I'd bet that you need to use the other valve cover as the PCV source. Maybe Mike Norris will chime in...

Or: any chance you could pick up an LS6 valley cover?

jp

[Mike Norris]

Hey All,

As John mentioned the passenger side is the fresh air inlet and you can use the blocked off nipple at the rear for to the catch can then the PCV valve and then to the intake port. When doing this remember that the nipple on the passenger side needs to be opened to fresh air, preferably after the MAF sensor if equipped, otherwise a big vacuum will be put into the crankcase and cause more issues.

You may also want to check your tune if it was done with no PCV originally and now adding one as now there is a possibility of it running slightly leaner depending on the install.

Hope this helps. Thanks John!!

Mike Norris