Any gains or benefit from a vented/catch can setup?
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Any gains or benefit from a vented/catch can setup?

Image is from the Swanson Racing setup, which is a guy local to me. But I am curious of any proven benefits? Does getting rid of the PCV and having an open setup like this make power?
Or are the benefits non-power related? Catches gunk that would normally pass back through your motor? Let me know what you think. I know he is using quality parts, I just want to make sure if I am spending my hard earned duckets, that it's not just for show and will provide a real benefit.
One of the outlets uses the stock PCV location and he machines another hole into the valve cover. Both go into that standard universal Moroso catch can with a breather on it. What are people's opinions on breather vs. no breather?
Thanks in advance for any technical information, dyno sheets, advice from people with actual experience and testing of similar setups.
Catch can just cleaner air going into the motor. I need to do it on my car use an fittings etc. Also if you are going to do this I would do an egr elimination. STM sells a nice block off plate with counter-sunk stainless hardware. I'll take some pics and post up tonight before I put my throttle body back on.
some argue that the vent plumbed into the intake (like stock) is beneficial to lubricating the turbo. But really it just ends up being a mess inside the intercooler pipes and intercooler, which I would think impedes flow. Then what does make it to the motor gets burned, which isnt optimal either. I think a catchcan setup will eliminate the pcv valve. If so, thats another plus. When a pcv valve goes bad, it causes oil leaks elsewhere, since the pressure has to go somewhere (valve cover gasket, front/rear seals, oil pan, etc...)
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I mean my car is running great, so maybe I should just leave it well enough alone. I figured before I get my valve cover coated I would look into this, but if it's not going to provide any real benefit I don't want to spend 300+ on some bling.
I drain crap out of my catch can every month. I think as long as your not routing this crap I'm removing back into your intake manifold your good, be it vented or routed back. I read it can lower octane rating over time and really gunk up your manifold.
except this method isnt sending any clean(er) air back into the motor..or air period.
its just venting to atmosphere.
for a daily driver, moderate boost, moderate rpms, and not all out hp...you wont notice a thing w/ it.
this is good for people with excessive crankcase pressures, blowing out dipsticks, running very large amounts of boost, etc...
you are just allowing the motor to vent its pressures at WOT instead of retaining it w/in (via PCV).
i run my setup vented to atmos. 1 -10 line dumped to the ground, and the other port just -6 dumped to ground.
on a built motor and lots o' boost it sprays oil vapor all over the place at WOT.
every car that i race and beat, they ask what's wrong with my car as its spraying oil all over their car
and no..motor isnt blown.
if you remove the pcv and vent, you lose the ability of it 'sucking' at vacuum, helping create a better seal on the rings, and longer lasting motor (talking long term)...so thats mainly the neg. side of venting.
is it a nice mod? yes, if its a race car or pushed really hard.
is it a worthwhile mod? not unless its a race car or pushed really hard, or can do it for very cheap on your behalf.dont expect hp out of it (though you can argue itll release 1-2hp under heavy load/boost apps)
also, if you are MAF and not SD, you may have air metering problems.
its just venting to atmosphere.
for a daily driver, moderate boost, moderate rpms, and not all out hp...you wont notice a thing w/ it.
this is good for people with excessive crankcase pressures, blowing out dipsticks, running very large amounts of boost, etc...
you are just allowing the motor to vent its pressures at WOT instead of retaining it w/in (via PCV).
i run my setup vented to atmos. 1 -10 line dumped to the ground, and the other port just -6 dumped to ground.
on a built motor and lots o' boost it sprays oil vapor all over the place at WOT.
every car that i race and beat, they ask what's wrong with my car as its spraying oil all over their car
and no..motor isnt blown.if you remove the pcv and vent, you lose the ability of it 'sucking' at vacuum, helping create a better seal on the rings, and longer lasting motor (talking long term)...so thats mainly the neg. side of venting.
is it a nice mod? yes, if its a race car or pushed really hard.
is it a worthwhile mod? not unless its a race car or pushed really hard, or can do it for very cheap on your behalf.dont expect hp out of it (though you can argue itll release 1-2hp under heavy load/boost apps)
also, if you are MAF and not SD, you may have air metering problems.
Last edited by norcalSRTrida; May 26, 2010 at 10:47 AM.
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its a moroso can for 89$, w/ 50$ in lines and fittings w/ the stock port drilled out and welded.

and no, you wont see any 'noticeable' benefit. just get a nice baffled sealed CC
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Well the AN fittings and lines bump the price up quite quickly. Argh I guess I'll leave it alone. I'm not running insane boost (28psi) and don't want to go looking for a way to create problems for myself on a car that's already running well.
How is it not 'sending' cleaner air per say? Hose from valve cover goes to intake which the turbo sucks up pushes through the intercooler / piping which goes into the intake manifold which goes into the motor. And quit being cheap and buy a can to dump the oil in and not all over the ground.
i spent maybe 80 bucks total using a moroso vented can. i didnt use AN fitting and braided lines but my setup is very neat and clean and does what its supposed to. everytime i drian and see what would have been in my intake/ ic/ motor ect. i smile. and i didnt ge rid of the pcv valve. i dont believe thats a good idea. could be wrong though.
IMO its worth it to keep the intake tract clean. Plus under wot the PCV closes so any venting is done through the breather straight into th einlet of the turbo, this blow by air can increase knock counts and rob some power. If you have a VTA catch can you should change oil more frequently tho.


