Mighty Mouse Can 
Another Pcv Question
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Teching In
Joined: Oct 2022
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Another Pcv Question Hey guys, just some background to start, I have an 89 Camaro, lm7/700r4 swapped. Was incredibly reliable N/A and proves to be ok after installing a vs racing cast 7875. The build is basically to a T a copy of sloppy stage 2.
The problem I'm having is I can't get my catch can routing figured out. I currently have the Dr. Side valve cover running to the catch can with a check valve, from there I have a hose from the catch can to the intake again with a check valve, pass. Side valve cover hose barb is open intended to be a breather. What's happening is under load I'm pushing my dipstick out and squirting oil everywhere. As well as out the pass. Side valve cover. I've tried a few different configurations with no luck. Any one got ideas what's going?
Something I should mention is I have an oil scavenge pump returning oil from the turbo into the Dr. Side valve cover. (front of the valve Cover not into the pcv) don't think this would cause issues but maybe?
Any help is greatly appreciated. Thanks in advance!
The problem I'm having is I can't get my catch can routing figured out. I currently have the Dr. Side valve cover running to the catch can with a check valve, from there I have a hose from the catch can to the intake again with a check valve, pass. Side valve cover hose barb is open intended to be a breather. What's happening is under load I'm pushing my dipstick out and squirting oil everywhere. As well as out the pass. Side valve cover. I've tried a few different configurations with no luck. Any one got ideas what's going?
Something I should mention is I have an oil scavenge pump returning oil from the turbo into the Dr. Side valve cover. (front of the valve Cover not into the pcv) don't think this would cause issues but maybe?
Any help is greatly appreciated. Thanks in advance!
What size are the lines and what kind of can?
I had similar issues when running over 10 lbs. and 3/8" PCV lines.
This configuration was used on a Mighty Mouse PCV Can and should be as follows dependent on boost level, more boost needs more flow in the PCV system.
-10 or -12 AN Line from engine to Catch Can, either valve cover or valley cover will work, no check valve, this line provides the necessary flow to the catch can when at WOT to relieve crankcase pressure.
3/8" line with inline check valve to throttle body or turbo intake, this line provides vacuum to the crankcase during normal operation but closes when boost is present.
Air filter on valve cover or valley cover, I'd use 3/8" hose from said valve/valley cover to a filter remotely located, this filter provides the clean air intake for the system but should not be part of the venting process under boost.
This configuration was good for me up to 14 lbs. and 700whp on my street car.
I had similar issues when running over 10 lbs. and 3/8" PCV lines.
This configuration was used on a Mighty Mouse PCV Can and should be as follows dependent on boost level, more boost needs more flow in the PCV system.
-10 or -12 AN Line from engine to Catch Can, either valve cover or valley cover will work, no check valve, this line provides the necessary flow to the catch can when at WOT to relieve crankcase pressure.
3/8" line with inline check valve to throttle body or turbo intake, this line provides vacuum to the crankcase during normal operation but closes when boost is present.
Air filter on valve cover or valley cover, I'd use 3/8" hose from said valve/valley cover to a filter remotely located, this filter provides the clean air intake for the system but should not be part of the venting process under boost.
This configuration was good for me up to 14 lbs. and 700whp on my street car.
You could also run 10AN or 12AN lines of the valve covers to a couple of breather cans and cap off the intake and throttle body. Either buy valve covers that have the AN fittings or weld some on yourself.
Works great, no fumes and have yet to have to empty it.
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Thread Starter
Teching In
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What size are the lines and what kind of can?
I had similar issues when running over 10 lbs. and 3/8" PCV lines.
This configuration was used on a Mighty Mouse PCV Can and should be as follows dependent on boost level, more boost needs more flow in the PCV system.
-10 or -12 AN Line from engine to Catch Can, either valve cover or valley cover will work, no check valve, this line provides the necessary flow to the catch can when at WOT to relieve crankcase pressure.
3/8" line with inline check valve to throttle body or turbo intake, this line provides vacuum to the crankcase during normal operation but closes when boost is present.
Air filter on valve cover or valley cover, I'd use 3/8" hose from said valve/valley cover to a filter remotely located, this filter provides the clean air intake for the system but should not be part of the venting process under boost.
This configuration was good for me up to 14 lbs. and 700whp on my street car.
I had similar issues when running over 10 lbs. and 3/8" PCV lines.
This configuration was used on a Mighty Mouse PCV Can and should be as follows dependent on boost level, more boost needs more flow in the PCV system.
-10 or -12 AN Line from engine to Catch Can, either valve cover or valley cover will work, no check valve, this line provides the necessary flow to the catch can when at WOT to relieve crankcase pressure.
3/8" line with inline check valve to throttle body or turbo intake, this line provides vacuum to the crankcase during normal operation but closes when boost is present.
Air filter on valve cover or valley cover, I'd use 3/8" hose from said valve/valley cover to a filter remotely located, this filter provides the clean air intake for the system but should not be part of the venting process under boost.
This configuration was good for me up to 14 lbs. and 700whp on my street car.
Currently I'm running 3/8 line from valve cover to catch can. Just throwing ideas at the wall I ran both valve covers Into one line into the vented catch can still with a line from can to intake with a check valve. This produced a really good result however I'm gurgling oil out of the filter now so I'm assuming something isn't right. The plan was to put an air filter into the oil filler as a breather. But yea I'll definitely try some bigger line and bungs on the valve Cover and hope that does it. Of all the stuff I've done to this thing in last year the pcv system is the last thing I expected to throw such a wrench into things 😅
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Verdad Gallardo Currently I'm running 3/8 line from valve cover to catch can. Just throwing ideas at the wall I ran both valve covers Into one line into the vented catch can still with a line from can to intake with a check valve. This produced a really good result however I'm gurgling oil out of the filter now so I'm assuming something isn't right. The plan was to put an air filter into the oil filler as a breather. But yea I'll definitely try some bigger line and bungs on the valve Cover and hope that does it. Of all the stuff I've done to this thing in last year the pcv system is the last thing I expected to throw such a wrench into things 😅
Depends on the can, if its vented to atmosphere then a couple of -08 or -10 lines off each valve cover should be sufficient, PCV cans one large -12 line will be sufficient.
Thread Starter
Teching In
Joined: Oct 2022
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I'll give that a shoot! Thanks a bunch!