Catch can plumbing

[sssammm]

My brain is getting frazzled here, the normal ccv is done by; passenger side valve cover to airbox, to let in fresh air, the drivers side valve cover to vaccum in inlet manifold.

The most popular catch can setup I have seen on this site is: Left valve cover to T piece, right valve cover to the same T piece and a single pipe from the T piece into the catch can.

now I have done this and Im getting overflow on the can, now from what I see, having both valve covers connect and run to a single pipe into the can is conflicting, would it not be better by having the passenger side vlave cover
air filtered, and the drivers side valve cover go to to can, then plumbed from the can back to the inlet manifold, this way seems to complete the circle yet still catch oil in the can?

any advice would be welcome

sam

 

[Shandon]

Hey Sam , I have a system that each side vents into one can. The only thing they share is the overflow can. Near the bottom of this thread is the same setup I have. You will notice that two separate lines go from each valve cover into the vented can. It works great. http://forums.viperclub.org/threads/658152-Oil-Catch-can?highlight=exotic+engine+catch

 

[sssammm]

so you have plugged and bypassed the vacuum?

I think my problem is I have tall valve covers, the fittings are right at the back, and the baffling is minimal

 

[Steve M]

What type of can? If you are running a vented can with a breather filter on top, you can connect both valve covers to the catch can, and you'd plug both the vacuum source and the fresh air make up line that comes from the air box. If you are running a non-vented can, you will run one valve cover into the can, and the other end goes to the vacuum source. You'd leave the fresh air line in place for the make up air.

 

[sssammm]

I got a vented can, both valve covers run into a T. and then 1 pipe to the can, have plugged the vac and have no airbox line, have the Hennessey twin airfilters, would I be better getting rid os the T and running individual hoses direct to the can?

this sound a better deal " running a non-vented can, you will run one valve cover into the can, and the other end goes to the vacuum source. You'd leave the fresh air line in place for the make up air".

 

[Steve M]

The t-fitting vs. individual hoses shouldn't make a difference. Do you still have the PCV check valve in place? If I'm not mistaken, that needs to be removed when running it like you are.

As for the non-vented can, you won't get 100% of the oil out of the crankcase vapors running it this way...just kinda the nature of the beast. You'll get most of them out, but not all like you can if you run a vented setup.

 

[sssammm]

Gen 3 dont have a PCV they have just CCV

 

[Shandon]

Not sure what Valve covers you have? I don't see a problem with having a T setup like that Saam. As long as the hose size is adequate that should be fine.

 

[Steve M]

I'd think it'd still have a check valve in there somewhere...otherwise, it'd end up pulling too much vacuum at idle.

 

[sssammm]

I think im going to try the 2 pipe vented with a return to the vac with a check valve

 

[Tail lights]

Hey Sam, if you're tracking your car, and the idea is to keep oil out of your air box and intake manifold and motors combustion chamber, you need to ditch the engine vacuum source (PCV or CCV) completely and run both valve covers to a catch can with a breather and plug the hoses the go between the motor and the air box. Pulling vacuum from one valve cover and a breather on the other is a good idea on a street car that doesn't see wide open throttle. At wide open throttle is when the Viper gets all that blow by, vacuum is at 0, all that oil and air would and does just blow out back into the air box.

 

[sssammm]

Thats what I have, both valve covers plumbed to a vented catch can, plugged vac vent, drive 10 miles catch can overflowing....driving me nuts, the only thing i can think of
is that I have fitted the tall x-metal billet covers, i think the position of the vent, right at the back has become an oil collection point, and the baffles are rubbish
see pic....

 

[Tail lights]

Thats what I have, both valve covers plumbed to a vented catch can, plugged vac vent, drive 10 miles catch can overflowing....driving me nuts, the only thing i can think of
is that I have fitted the tall x-metal billet covers, i think the position of the vent, right at the back has become an oil collection point, and the baffles are rubbish
see pic....

Wow, thats messed up! Just an idea, plug the holes in the back of the valve covers, and install some breathers on the top in the center of the valve cover, Jim at Exotic Engine Development makes some good ones, and so does AC performance . I've got them on my car and they work great. Although they are used in conjunction with the stock valve covers and the big battles.

 

[Drew]

Dont doubt your experience sam but Im experiencing the exact opposite. Before I had a vented catch can installed, I would use a full litre on a track day.
When the intake was pulled it was coated in oil as suggested by others when I was concerned about drop in performance by the seat of my pants feel.
It was suggested the octane level of the 94 octane fuel i was using was being reduced due to the added oil in combustion.
With a vented 2 pipe (1/2" ID) catch can and no check valve (PCV), plugged vacuum ports on air box and intake.
After 3000KM there is not a drop of oil or moisture in my catch can and the stock front ports of the GEN IV valve covers where used.
I no longer consume oil between oil changes. And performance has never been better.

 

[Tail lights]

Dont doubt your experience sam but Im experiencing the exact opposite. Before I had a vented catch can installed, I would use a full litre on a track day.
When the intake was pulled it was coated in oil as suggested by others when I was concerned about drop in performance by the seat of my pants feel.
It was suggested the octane level of the 94 octane fuel i was using was being reduced due to the added oil in combustion.
With a vented 2 pipe (1/2" ID) catch can and no check valve (PCV), plugged vacuum ports on air box and intake.
After 3000KM there is not a drop of oil or moisture in my catch can and the stock front ports of the GEN IV valve covers where used.
I no longer consume oil between oil changes. And performance has never been better.

Drew, I agree with you 100 percent, I wonder if Sams problem is because he's pulling his vans off the back of the valve covers, Maybe there's a pool of oil back there and blowby is actually pushing the liquid into the can. it's good to hear your system is working so well, FYI The ACR's Plug the front port on the valve cover, And tap into the valve cover it in the center on the side. See you at the ridge.

 

[sssammm]

Im going to put my oem covers back on, see if that makes a difference, then ill know if its the new covers, think ill also try tapping the side

 

[Drew]

Tail lights, I have seen the location of the ACR connection points. The fact I get no oil collection in the can what so ever, I see no reason to mess with my valve covers. Not sure why no oil enters the can, hose size?, can fabrication? Idk. Keep checking it expecting something.
Hope to make it to the ridge June 28/29 and/or July 22 and 26
See you there hopefully.

 

[sssammm]

OK, going back to basics, I have put back the original valve covers and spacers, got rid of the pipework and am going to run
2 separate pipes the the new billet can, that has a vented oil cap (fits great)

need a few fittings which i hope to get tomorrow and start it up saturday and cross fingers
sam

 

[Steve M]

Question on the vented cap...does it allow air to flow both into and out of it? It needs to do both in this case. The typical vented cap like that will only let air out, not back in since it isn't filtered.

 

[sssammm]

yes, the cap is quite ingenius it is filtered and lets air in and out

 

[sssammm]

Ok Chaps, thanks for all the help, but the problem has been solved, and im pissed, I put back the original rocker covers, plumbed in exactly the same,
Ive just been out for 25 miles, and there is not even a spot of oil in the can, Its was the useless baffle in the X-Metal alloy cover, so
Ive totally wasted my money.........

sam