oil catch can on an rb25det

[grimr33per]

hi,

what are the benefits of fitting an oil catch can? i know sweet f.a. about them and what they actually do.... the general idea i got is that they effectively remove oil from the air travelling between the two breather pipes by dumping the air into the can, the oil falls to the bottom, and the clean air returns to the breather.... is that more or less what they do or am I way off :-) are they worth getting, and what positive effects do they have?

any advice would be great.

[GTRgeoff]

r33per I use mine to remove the recirculating foul air that comes from the crankcase. Turbos get a lot of blowby the rings at high boost which is an AF mixture, exhaust gas and atomised oil from the stirring and stuff in the crankcase. These things are detonation inducers and lower potential max power and can bring on detonation. I vent mine from the catch can, through a filter, to the atmosphere and not back into the pre turbo/post airflow meter pipe. Recirculation is done for emissions so this is prolly illegal, but so should be pushrod v8's

Makes sense to me to get rid of the waste and I'm a Mechanical Engineer and was a Mechanic before that.

[grimr33per]

excellent, cheers man. so those little micro-pods on catch cans actually filter the air LEAVING the catch can, and without a can, the air from the crankcase just gets recirculated into the intake? ewww....... so correct me if i'm wrong.... but the two breather pipes from each side of the head both push their crap out back into the intake?

sorry for all the q's, i'm just trying to find out as much as i can about how they work, what they're good for, how to install one etc

[[SweN]]

Originally posted by grimr33per

so correct me if i'm wrong.... but the two breather pipes from each side of the head both push their crap out back into the intake?

at a guess, they should also be connected to a hose that comes from the block, and the air should go into the plenum?? im guessing. but thats whats supposed to happen for it to meet emissions regulations. dont have a car here at the moment to check for you

[Boostzor]

Here is the biggest thread on the subject from recently.

http://www.skylinesaustralia.com/forums/sh...r+oil+separator

All i can say is , GO THE COKE BOTTLE!!!!!

[GTRgeoff]

Your right about the coke bottle, keep the costs down. I race, and the only reason I keep my machines clean is to maintain cred at the track. Pretty cars generally don't get worked or have had too much spent to risk an off, while a filthy machine infers no pride, but each to their own.

Watch though if you start blowing heaps of oil out the breathers, means something bad like cracked rings, or pistons (4 of them)

I recall there is no crankcase hose though on a 33, but a return line from the turbo oil is there.