97VetteDan

I went ahead and installed a catch can not too long ago but still notice blow by collecting on the rear end. Did I install it correctly? What else can be done to eliminate the blow by collecting? LS6 Valley Cover? Eliminating the crappy LS1 PCV system somehow? I used to think a leak was to blame, but I had the car checked for leaks and none were found.

Here is my $6 catch can installation:






Here is what the blow by looks like:

Nasbluec5

I redid my entire pcv system
https://www.corvetteforum.com/forums...catch-can.html
Scroll down to post #8.

97VetteDan

Awesome man! I can't wait to do the same to mine.

The only thing is, I live in CA so everything I do needs to be SMOG/CARB compliant.

Will I have any problems from the state with this PCV mod? Thanks again!

Nasbluec5

Sorry I didn't see this until now. There should be no reason for this to fail. The pcv system is still very much intact. Just routed differently. None of the pcv system is venting to atmosphere, that's where they'd get you. You just can't remove your air pump like I did.

I've gone back since taking those photos and painted the separator black so it blends in to the engine. If you take your time and make it look professional no one would even bat an eye at it anyways.

Nasbluec5

12572717 Is the gm part number for the pcv valve. Give the parts store that number and they'll be able to cross reference it.

Big_George_S

I too live in California, Yes this is considered to be a modification to the engine that requires a C.A.R.B certification. My recommendation is to remove prior to your visual inspection, reinstall as original, inspect, then reverse.

Nasbluec5

By that logic you're saying that you couldn't install an ls6 valley pan on an older ls1. Guess it would just depend on your inspector.

David@MMS

there are 4 typical points for oil consumption

1 fresh air hose at air bridge, if you are making a lot of power or aftermarket engine components oil here can mean you need up increase system flow capacity
2 pcv return to intake manifold, this is the normal 'foul side' oil catch point
3 valvetrain, worn valves, guides, seals can allow oil down the valves
4 cylinder, worn,damaged, or improperly sized components here can allow excess oil above the piston

pcv related oil can be caught in a common can, clean side oil needs some extra measures, especially at high hp to avoid increasing crankcase pressure, which is my specialty.

I build custom systems for those interested Here is a typical c5 install

CTD

I had nothing but grief with various CC setups, then I stumbled upon David @ Mighty Mouse

My deal is High N/A & his CC solved many issue's. Such as blowing the dipstick out, blow by under the hood etc.

As a suggestion for what it is worth in David's photo I wrapped the CC in header tape to try & keep the temp down. I can post a photo if interested.

Nasbluec5

My $40 dollar set up is working great, not even a teaspoon of oil after 250 miles when before I was adding oil every 1000 miles or so. Not sure why this is such a big deal

STL Mike

OP, how are you sure that's blow by? Do you have any engine or exhaust mods to the car? Does the exhaust smell rich when is idling in one spot long? I had the same particulate on the bumper of my 95 cobra, but I had no cats and my tune was far too rich at idle.

David, I'm curious if you have any input to my CC setup. I installed a dual setup and eliminated the pcv on my 02 Z. At about 100 miles, the rear main started leaking, so I installed the pcv back with the dual cans. Leak is now gone.

I couldn't figure it out but while talking it over with some other engineer today I came across a reasonable scenario where the crankcase would be pressurized. During a WOT blast, there is no vacuum at the intake port. The blow by pressurizes the can like an accumulator, the 3/8 lines can't keep up and at this point the crankcase pressure is pushing gas into the intake via the catch can. Just after the WOT blast, the engine begins drawing vacuum as it returns to idle, but again, the 3/8 line can't keep up so the can is releasing pressure into both ports. The crankcase is momentarily pressurized until the intake vacuum can catch back up. This momentary pressure pushes oil out my rear main seal.

Thoughts?

STL Mike

I'd like to have a look please.

97VetteDan

I just assumed it was blow by but now that I think of it, there are times I notice the exhaust smelling rich.

All my mods are:

B&B Exhaust, Cowl Hood, Vortex Ram Air Intake, SS Braided Brake Lines, High Performance MAF, Cross Drilled and Slotted Rotors, HPP3 Tune, True C5 Z06 Rear Brake Ducts, KYB Gas-a-Just Shocks, Custom Sound System, C6 Z06 Wheels

If it is in fact running rich, what needs to be done to alleviate this problem? Some kind of custom tune to lean it out?

97VetteDan

I appreciate the information. I already have to put the stock air box back on every two years for smog, I suppose switching the pcv up wouldn't be too bad. Still, it's a hassle I'd prefer not to deal with. C.A.R.B needs to be abolished. All they do us cause headaches. The worst part of it is, all the crap car hobby killing legislation starts in CA, and eventually infects the rest of the states. Go away C.A.R.B!

David@MMS

it depends on the can but it is completely possible. if you completely sealed the system from any ventilation point other than the intake manifold absolutely could be a big problem, at least you had that one.

one can or five you always need a way for pressure to leave the system, in every driving condition. if you had oil consumption or crank pressure conditions leading you to thinking two cans were the answer my PCV can (by itself) can take care of both for you up to 1500hp. (selling the two cans may pay for it!)

STL Mike

My guess is either your cats are worn out and need replaced or the fueling needs leaning in the tune. I'm not smart on the HPP3, but doing a quick search it looks like folks report that it changes spark advance (adds timing) and PE (Power Enrich) vs RPM table, which appears to be fueling . I've not found anyone report stellar results. I would recommend a professional tune thru someone who can measure AFR thru the entire RPM band and tune the car accordingly.

Are you able to remove the tuner and the tune, return the car to stock tune and recheck if the particulate remains?

STL Mike

The car is setup now as it was from the factory with the PCV, except there is a catch can inline on each circuit:

Pass. valve cover to intake
Lower manifold to intake (with PCV allowing flow only to intake)

97VetteDan

I've attempted to remove the HPP3 tune in the past and I diddn't notice any difference in the particulate collecting. I think I would want to try a tune first before replacing cats. Would you happen to know how much a tune might cost me and any reputable tuners around Sacramento, CA?

wcsinx

If you have enough oil coming out of your exhaust to leave black specs on your bumper, then you'd also be leaving a huge white smoke screen everywhere you go. I'm on board with the rotted out cat theory.

STL Mike

I have no idea about that area. You'll have to do some research.