View Single Post
Old 02-24-2011, 12:14 PM   #6867
Xanthos
PWA Relapse
 
Xanthos's Avatar
 
Drives: Formerly-Stick
Join Date: Mar 2008
Location: Oklahoma
Posts: 12,588
Quote:
Originally Posted by PoorMansCamaro View Post
i'm so confused about all this pcv/ncv stuff. i'm hoping once i get it in and read the instructions, i'll know what i'm doing. lol
Haha. Maybe this will clear it up:

The crankcase ventilation system is designed to pull filtered air through the crankcase and into the combustion chambers, where excess gases can be burned in combustion. The goal of a breather/catch can setup is to keep this system in place, but keep oil out of the combustion chambers. A catch can alone cannot accomplish this, because it only filters oil out of the positive side of the system. This catches most of the oil, because its the normal direction of flow for the system. However, during zero vacuum (such as at WOT) the system can sometimes reverse flow (meaning air flows from PCV to NCV). Because of that, a catch can wouldn't help anymore. Replacing the negative side with a breather makes it to where air flowing in reverse does not enter the intake air, so no oil can enter combustion that way. Its not emissions legal, though, because any crankcase gases are simply expelled into the atmosphere.

I think the only way to be emissions legal on it would be to have two catch cans, one for each side of the system.
- X

P.S. - Plus, it looks cool.
__________________

2017 1LT/RS A8 Hyper Blue Metallic

Xanthos is offline