Catch can question..which is better?

[nevaland9]

Ive heard better vac helps seals the rings better and makes the motor happier but which was is the best? Just putting a breather on dosnt seem too smart.

Which way is the best way to run my catch can and why?

this way looks the easiest.
http://www.speedyzx.com/SoCal72702/DSCF0066.jpg

and theres this way
http://www.street-solutions.com/_images/engines/freshalloypic3.jpg

i heard this way is the best
http://www.nismoclub.ca/Picture194.jpg

help me out

[DJ_Sunrise]

When I get mine, Im going to mount it on the drivers frame rail, that way it doesn't clutter up the engine bay.. Some guys just run a line straight through with no can.. but that makes the underside messy :rant: Just an idea.

-Bart

[SlowCoupe]

i think the 3rd way is best.

thats assuming the line comming off the tee goes to a can and a line from the can goes to the turbo intake.

thats how i have mine hooked up.

[smelly240]

mines the 3rd way...

[jilo]

on a redtop or basically any other sr it should be a line from crank case->catchcan->t->post maf intake

[1320_power]

quoted from a friend in japan

here is one hose that goes from the valve cover to the intake manifold with a check valve in place called a PCV valve, positive crank ventilation. Basically this sucks the pressure out of the crank case when not under boost. When under boost, boost pressure closes the PCV valve. If this valve was not there and it was a direct hose, then it would over pressurize the crank case.

Then thee is another hose that goes from the valve cover to the intake pipe of the turbo. When under boost, the turbo creates a vacuum in front of the compressor inlet, sucking the pressure out of the crank case.

At high RPM is when you get the most blow by and crank case pressure. When there is no catch can where from the valve cover to the turbo intake pipe, oil along with air get sucked out of the crank case. This oil gets sucked right into the turbo and makes it way to the intercooler. So to alleviate this, a catch can is installed.

The hose goes from the valve cover, to the catch can. Then another hose goes from the catch can to the turbo intake pipe for the vacuum effect. So at high boost high rpm, the catch also has a vacuum.

The other fitting I would say its for draining the catch can. Its not necessary to have the vacuum effect for crank ventilation. but that more for people who do not run intake pipes on their turbo., or a PCV valve on their intake manifold. The hoses just dump to the atmosphere.