Turbo and Supercharger discussion
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By teal_dx
#3138 I'm going to be installing a catch can.

after doing some research, I've narrwed it down to a couple of options:
1. Valve cover and crank case lines to a can with a vented filter on the top.
2. Valve cover and crank case lines to a sealed can with a tube exiting, routed into the exhaust with a slash cut tube.

I've excluded the setup of running a line from the top of the can back to the intake because under boost, air would be forced into the catch can and back into the crank case & valve cover. I could install a check valve in the line though, but seeing as the motor will still see boost most of the time rather than vaccuum, it would defeat the purpose.
I've also excluded the idea of running a tube back to the intake (pre-turbo) for vacuum because I really don't want to put that air back into the system and chance gunking up the turbo/FMIC if the tank ever gets too full.

So back to 1 and 2, I'm wondering has anyone ever had success with the slash cut method? It's a lot of work to try it and not have it work as well as it should. There are lots of variables with the way it is set up that can determins how well it works.
So I'm leaning toward #1 vented catch can with a small air filter on the top.
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By teal_dx
#3140 pics for reference:

#1 Vented catch can:
Image
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By ohDirka
#3147 on our drag car we ran it to the exhaust, and thats what im planning on doing to my rex
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By teal_dx
#3152
d15kid wrote:on our drag car we ran it to the exhaust, and thats what im planning on doing to my rex


Can you give me the details or pics of the setup?

I'm wondering about the angle & placement of the slash cut to get it to work right. Also, what dia. tubing to make it work best?
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By ohDirka
#3783 sorry this took so long but i checked it out and we took like a 3/8 in tube can cut it at an angle then welded it in. then we ran rubber hose down to it..but id suggest doing it with steel braided tubing for an everyday driver..we were only runnin for 30 sec and going a 1/4 mile.. ill take pis of it next time i have to wrap the headers
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By teal_dx
#4484 well I went the economy minded route and bought a Greddy knockoff from ebay. it should be here this week. It does not have a breather on the top of the can, but I have a breather so I can modify the can to make it work. Then down the road if I ever do the slash cut setup, I'll just remove the breather and run a SS braided line to the down pipe.

Image

not bad for $30 + 14 s/h
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By boxcarracer0260
#4547 i have something similar to the pic above on my car but i am not boosted and it works great.