Alot of us know what the pcv system is and what it does, but we still just slap a breather on the valve cover when we boost and call it a day... well guess what, WE'RE FUCKN UP!!!! After studying (or looking at) and debating ---- on H-T, I have come up with a way to use the pcv system much more effeciently, add a little hp, and make life a whole lot easier on piston rings.

First let me explain how the stock pcv system works:



Basically, vacuum on the manifold sucks blowby out of the block and is regulated by the pcv valve. However, at full throttle (N/A), their is hardly any vacuum to suck, and on boosted motors, the pcv valve is closed all the way, so your delicate piston rings have the added job of pushing all that air/pressure/blow-by in the crankcase all the way through the oil passages and up through that small little whole on your valve cover breather. This is not good, especicially when u realize that the valve cover hole (breather) is supposed to be taking air in (breathing), not out. In addition to that, u are sucking all that good oil vapor into ur manifold at idle/cruising. After browsing for a remedy I found this on Larry Endyn's site:



Very similar to what I had in mind. So i decided to go out and buy a catch can similar to above, and make a similar system, when I realized, that most of us w/95 and older Hondas already have a catch can on the back of our motors. The only problem is, it is "Plugged" by the pcv valve when we hit boost... My remedy: get rid of the pcv valve/vacuum system and replace it with a "breather" system. This way, when pressure builds up in the block, it can just shoot out the catch can/breether instead of having to go through the oil passages and out the valve cover.



In addition to making life easier on rings, etc., this will also free up some power. V8 guys make 15+hp when they add a vacuum pump to their crank case, so we should see around that or more in our high revving or boosted motors. Nascar and Most Pro Drag cars (even imports) have some sort of vacuum/venturi (spelling?) system that pulls blow-by out of the crankcase to reduce hp losses due to windage. Will post more pics and results later...

 

why not just unplug your pcv valve and tape a coke can on it?

 

same ----. just what i'm gonna do

 

Might I throw up this illustration for people who are confused and want to go turbo. A lot of people don't realize this ---- and end up getting some mad blowby because they are double forcing air into the pcv system with the boost (leaving it hooked up like it came stock). I ripped this from the g2ic faq found in the links section of the website - gotta give credit where it's due.



Please note that I refer to this as the "dsm way" since the dsm is hooked up very similar, just have to go out and buy that little breather filter. A catch can is an absolute must, if anyone would like to do a writeup for a HMT style one that is half way decent, post it over in the FI forum and I'll sticky it for a little while.

-ryan

 

hmm...i don't know if spitting the blowby into your intake stream pre-turbo is good for the blades...

 

It's not going into the intake. It stays in the catch can.

 

This would be pimp

 

Catch can doesn't seperate ALL of the oil, just catches most of it