catch cans vs breather cans
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Joined: Mar 2012
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From: South Florida
It will work for N/A also. The line from the TB is where the metered air is drawn from. Then through the engine, out to the catch can, into the intake manifold port. During normal driving, part/low throttle, you should be getting the vacuum from the intake sucking the clean/metered air from the TB port into the manifold port. When you go WOT your intake manifold vacuum is gone pretty much. Although your crankcase pressure will be at it's highest from blow-by. On a normal PCV system the pressure goes out every point it can. Why sometimes you may see oil from the clean air port on/inside the TB. This is where the vent, on the can, comes in to play. At the point of no manifold vacuum, & crankcase pressure, the breather opens up to let the excess pressure out. Instead of just being forced through any line it can.
I run a vacuum pump. Didn't want any more oil in intake/through motor. The release valve is set to around 15 inches of vacuum. As that happens at full throttle high rpm which the engine loves. If you ever notice looking under LS motors & notice the "seeping" oil from around the pan. This is usually caused by crank case pressure. As on my car there is no oil seepage spots anywhere as the crankcase is usually always under a vacuum.
I run a vacuum pump. Didn't want any more oil in intake/through motor. The release valve is set to around 15 inches of vacuum. As that happens at full throttle high rpm which the engine loves. If you ever notice looking under LS motors & notice the "seeping" oil from around the pan. This is usually caused by crank case pressure. As on my car there is no oil seepage spots anywhere as the crankcase is usually always under a vacuum.
Last edited by SoFla01SSLookinstok; Jun 2, 2018 at 11:32 AM.
Thread Starter
Joined: Mar 2011
Posts: 3,699
Likes: 168
From: Wilmington, DE
It will work for N/A also. The line from the TB is where the metered air is drawn from. Then through the engine, out to the catch can, into the intake manifold port. During normal driving, part/low throttle, you should be getting the vacuum from the intake sucking the clean/metered air from the TB port into the manifold port. When you go WOT your intake manifold vacuum is gone pretty much. Although your crankcase pressure will be at it's highest from blow-by. On a normal PCV system the pressure goes out every point it can. Why sometimes you may see oil from the clean air port on/inside the TB. This is where the vent, on the can, comes in to play. At the point of no manifold vacuum, & crankcase pressure, the breather opens up to let the excess pressure out. Instead of just being forced through any line it can.
I run a vacuum pump. Didn't want any more oil in intake/through motor. The release valve is set to around 15 inches of vacuum. As that happens at full throttle high rpm which the engine loves. If you ever notice looking under LS motors & notice the "seeping" oil from around the pan. This is usually caused by crank case pressure. As on my car there is no oil seepage spots anywhere as the crankcase is usually always under a vacuum.
I run a vacuum pump. Didn't want any more oil in intake/through motor. The release valve is set to around 15 inches of vacuum. As that happens at full throttle high rpm which the engine loves. If you ever notice looking under LS motors & notice the "seeping" oil from around the pan. This is usually caused by crank case pressure. As on my car there is no oil seepage spots anywhere as the crankcase is usually always under a vacuum.
so the vent is very beneficial for an FI motor, but also has its benefits on an n/a motor too. so it is still better to spend double on the mighty mouse can than a regular can without a vent if you can swing it. hopefully this will cut down on my oil in the intake.
Thread Starter
Joined: Mar 2011
Posts: 3,699
Likes: 168
From: Wilmington, DE
