Thread: Breather filter on VC?

Just curious on facts and everyone's thoughts about using a breather filter on the valve cover to vent the crankcase.

I usually see this when adding a turbo to a DE to prevent pressurizing the crankcase. Personally, I ran a line just after the air filter, before the turbo.

I've heard people say there's no ill effects, to some saying it will cause vac leaks. Just looking for a definitive answer to this.

Anyone care to chime in?

i have a breather on mines. no effect on it was so ever but im going to recirculate either way with my new ic pluming.

the breather gets oily lol might as well recirculate it, i did on my new piping.

I check my hose going from the intake to the vc religiously. I haven't spotted any oil yet, but who's to say that won't change.

I'm thinking a catch can is in order. I removed the stock one because it was shot....plus it looked hideous.

Does anyone have their vent setup like mine? And have you had any issues?

i would rather run a catch can to vent the crankcase

Are most of the aftermarket catch cans the type that needs to be emptied periodically? Or are there some that drain on their own? Most of the ones I've looked at don't mention anything about it.

they would need to be emptied, however it really depends on how much your car is going to expell the oil into the catch can like ive put 10k on my engine and its fully built however only seen very little oil in my catch can. so i emptied it once in 10k miles and it was nowhere near full at all, so it really depends on the engine

A breather filter is acceptable but doesn't help ring seal as much as recirculating (pre-turbo). Adding a catch can before the breather filter helps contain the small amount of oil that will inevitably vent and keeps the filter clean.

Recirculating with factory valve cover and crankcase catch cans is usually fine. Add an additional catch can if you want to be super safe before recirculating. Recirculating without any catch cans will coat the turbo intake, turbo, charge pipes and most importantly the intercooler with oil residue. Oil residue inside the intercooler lowers its effectiveness.

You should pay attention to the flow capacity of any catch cans as restricted ventilation causes many problems.

Sounds like I need to put that catch can back on. At least until I can get one that's not such an eyesore.

yea i recently removed my factory catch can because i was running the gredddy catch can, best move i made, but if yo dont have a greddy or any kind of aftermarkt can then keep the oem one