Crankcase venting?
#1
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Crankcase venting?
I have read many different threads about vent/catch can set ups but still don't know what will be best for my build.
I planned on running 2 -10 or -12 lines one from each valve cover to catch cans then back into the fresh air side of the turbos I could also pull from the valley cover if that is a better way?
The build=
Lsx427
Sheet metal intake
Twin 67mm turbos
Mostly street with some 1/4 time
1000+ who
No valve covers or valley pan yet until I figure out the venting a system!
I planned on running 2 -10 or -12 lines one from each valve cover to catch cans then back into the fresh air side of the turbos I could also pull from the valley cover if that is a better way?
The build=
Lsx427
Sheet metal intake
Twin 67mm turbos
Mostly street with some 1/4 time
1000+ who
No valve covers or valley pan yet until I figure out the venting a system!
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I would rather not dump into the exhaust even though i seen it done many times and it works. Really just wondering if the valley or valve covers is best to pull from and shooting the fresh air side back to the air filters will provide good evac.
#5
I have 2 -8 out of valve covers and -8 out of valley cover. I use to have all 3 going into 1 mightymouse can. However I was having issues with the can filling quickly. So i ran the 2 out of the valve cover into the can and ran the 1 valley cover into a separate can. Works great only thing I would change is add some sort of baffle to the valley cover hole. I forgot to do it and i get a little more oil than id like in that can. And i have had no oil/water in my valve cover can since i did this setup ..
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#9
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i have 3 strategies for this
for an all out 'race' car , and no air filter where you change the oil often and need maximum flow, a tank to catch any mist in the fumes exiting the crankcase is a good solution
for cars running air filters, there is a slight vacuum created behind the air filter, this can be taken advantage of by using this 'draft' to scavenge the crankcase, this will also eliminate oily smells from an open system
for cars needing to pass inspections, or daily drivers, a maximum effort version of the factory intention 'pcv' system is best. there is are reasons believe it or not why all cars start off with a pcv system.
you have to keep in mind in your connections, that the more powerful the engine the more breathing room it will need. you cannot breathe a 1khp engine through a stock valley plate for example. for a real pcv system you need to source fresh outside air, to be constantly running through and picking up contaminants on the way to being either caught or ingested by manifold vacuum. too much crank vacuum will cause air to pull past engine seals, mains normally, so a metering device such as a real pcv valve is encouraged.
for an all out 'race' car , and no air filter where you change the oil often and need maximum flow, a tank to catch any mist in the fumes exiting the crankcase is a good solution
for cars running air filters, there is a slight vacuum created behind the air filter, this can be taken advantage of by using this 'draft' to scavenge the crankcase, this will also eliminate oily smells from an open system
for cars needing to pass inspections, or daily drivers, a maximum effort version of the factory intention 'pcv' system is best. there is are reasons believe it or not why all cars start off with a pcv system.
you have to keep in mind in your connections, that the more powerful the engine the more breathing room it will need. you cannot breathe a 1khp engine through a stock valley plate for example. for a real pcv system you need to source fresh outside air, to be constantly running through and picking up contaminants on the way to being either caught or ingested by manifold vacuum. too much crank vacuum will cause air to pull past engine seals, mains normally, so a metering device such as a real pcv valve is encouraged.
#10
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I run the standard check type PCV valve from the ls6 valley to the intake manifold. Then each valve cover is vented with -10 (larger the better) to a breather tank. This way you get PCV under normal driving vac conditions and have plenty of vent line under high blowby. Now the make up air under vac comes from the vented catch can and is not metered, but I never had a problem with a MAF car since it's a very small amount and fuel trims will cover it for the most part.
The only thing I don't like about pulling the air into the intake pipes on a compressor is the buildup of oil in the intercooler and pipes over time. I agree the tiny bit a vac you would get would be better than just a vented tank, but not enough for me to risk oil in the pipes, etc.
The only thing I don't like about pulling the air into the intake pipes on a compressor is the buildup of oil in the intercooler and pipes over time. I agree the tiny bit a vac you would get would be better than just a vented tank, but not enough for me to risk oil in the pipes, etc.
#12
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they are normally smelly and messy with just a breather on the valve cover
draft and pcv style catch cans generally do another job of clearing condensation and contaminants from the oil that can shorten oil life, tho i don't have any fancy charts to show for that one, probably same stuff OEM's are after.
draft and pcv style catch cans generally do another job of clearing condensation and contaminants from the oil that can shorten oil life, tho i don't have any fancy charts to show for that one, probably same stuff OEM's are after.
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they are normally smelly and messy with just a breather on the valve cover
draft and pcv style catch cans generally do another job of clearing condensation and contaminants from the oil that can shorten oil life, tho i don't have any fancy charts to show for that one, probably same stuff OEM's are after.
draft and pcv style catch cans generally do another job of clearing condensation and contaminants from the oil that can shorten oil life, tho i don't have any fancy charts to show for that one, probably same stuff OEM's are after.
Whats your preferred method to contact you? Im wanting to tell you my setup and get your opinions then place an order for a catch can setup. email? website? phone call? text? pm? lol lmk
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Another way I was told that works is Vent the valve covers to a can with a filter, then vent the valley to a different can that also has a line to your intake manifold port (add a check valve if boosted) which is similar to the way I thought would work but drafting it with the air filter.