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iceminion
03-06-2008, 07:46 PM
Will work with any turbo/supercharged car.

Problem:
Pressure in the crank case builds up while car is at wide open throttle (WOT) causing oil leaks. The stock vacuum system in our cars is designed to deal with this problem, -but- our cars are not stock anymore, they move more air, have more blowby, and have more problems.

Symptoms:
Oil dip stick pops out
Oil leaks from the oil cap
Oil leaks from the valve cover gasket
Oil leaks from the cam angle sensor gasket


(this assumes that you have a working PCV valve and have replaced the above gaskets before you do what I am about to suggest)

Conventional solution:
Use a breather filter, if that doesn't work, weld large AN fittings to allow air to blow itself out at a slower rate, thus decreasing the pressure in the valve cover to about atmosphere pressure (~15psi). I disagree with this solution, because it only allows the crank case to vent to atmosphere, it will never be @ atmosphere, always slightly above atmosphere, with air constantly escaping.

My Solution:
Much cheaper and easier then welding AN fittings to the valve cover, and I insist will work better.
A venturi vacuum pump creates a vacuum in the valve cover while under boost. (see picture).

I have been using this for over a week and it has worked great, my car idles better and no oil leaks anywhere!

If anyone wants me to build them one.

iceminion
03-06-2008, 07:59 PM
http://en.wikipedia.org/wiki/Venturi_effect

Super Bleeder!!
03-06-2008, 08:05 PM
How is this any better than pulling vacuum from the intake pipe before the turbo?

I doubt it is, or the factory would have done it.

iceminion
03-06-2008, 08:14 PM
I guess I should have been more specific about the applications for this pump.

stock cars with stock intake pipes are probably going to be ok.

cars with 4 inch intake pipes coming off the turbo have a problem.

Since the 4 inch intake pipe is such low restriction, there is absolutely no vacuum created by hooking a vacuum line up to the side.

I tested this with a boost gauge, didnt pull any vacuum at all.

again, this is for people who are having problems, if you are not having a problem, nothing to fix right?

Speedfreak
03-06-2008, 08:45 PM
I guess I should have been more specific about the applications for this pump.

stock cars with stock intake pipes are probably going to be ok.

cars with 4 inch intake pipes coming off the turbo have a problem.

Since the 4 inch intake pipe is such low restriction, there is absolutely no vacuum created by hooking a vacuum line up to the side.

I tested this with a boost gauge, didnt pull any vacuum at all.

again, this is for people who are having problems, if you are not having a problem, nothing to fix right?

Where did you place the boost gauge vacuum line? I'm wondering if it is placed directly in front of the compressor housing if it would work? I want to make crankcase vent system for mine as well. I'll play around with a thing or two and if anything works, I'll let you guys know.

Super Bleeder!!
03-06-2008, 09:27 PM
I guess I should have been more specific about the applications for this pump.

stock cars with stock intake pipes are probably going to be ok.

cars with 4 inch intake pipes coming off the turbo have a problem.

Since the 4 inch intake pipe is such low restriction, there is absolutely no vacuum created by hooking a vacuum line up to the side.

I tested this with a boost gauge, didnt pull any vacuum at all.

again, this is for people who are having problems, if you are not having a problem, nothing to fix right?

It pulled no vacuum at wot?

Shotgun!
03-06-2008, 10:32 PM
I remember that Raptor was using an old Ford Escort Diesel (Yeah they made a few of those) vacuum pump for his Talon's crank housing. Same idea, no?

Come to think of it, I still have one of those pumps. It's at the other end of this room...weird.

JET
03-06-2008, 11:31 PM
What is the white thing on the valve cover line, a catch can?

Raptor was going to use a mechanical pump. Those flow much more than this could. He was also going to tap into the block, since this is where you want the air coming out of, not the valve cover. There are a bunch of cars running a venturi style, but they normally use the exhaust pipe to create the venturi, not a tiny little vacuum line.

The biggest reason that people do the breather filter is because they don't want all that oily mess going back into their engine and IC, which yours still has. You are on the right track though.

iceminion
03-07-2008, 05:35 AM
the little white thing is a fuel filter, it collects oil like a catch can to keep the intercooler free of oil.

yes, a mechanical pump would probably work out pretty good also, but i would consider that overkill.

the stock PCV valve works great for off-boost conditions, and this is for only when you are boosting.

iceminion
03-07-2008, 06:09 AM
It pulled no vacuum at wot?

yes, I lost a bet with one of my gearhead friends, believe me, I was of the opinion that "this is a crazy idea and will not work"

Lets put it this way, I had the car setup just as it was stock, the turbo pulling on the crank case vent, I had oil leaks everywhere, but due to the (massive) change in diameter of the intake pipe, the stock vacuum line did not pull much(if any) vacuum, and I HAD OIL LEAKS.

all I am saying is this FIXED THE PROBLEM that I have always had, my first TSi AWD (stock) popped the dip stick all the time, and when i let my friends drive the car it would pop and send oil spewing up onto the underside of the hood, make a huge mess of things! I wish I had this then!