Venturi vacuum pump

iceminion · 03-06-2008

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

http://en.wikipedia.org/wiki/Venturi_effect

Super Bleeder!! · 03-06-2008

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

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

Quote:

Originally Posted by iceminion

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

Quote:

Originally Posted by iceminion

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

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

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

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

Quote:

Originally Posted by Super Bleeder!!

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!

iceminion · 03-07-2008

Quote:

Originally Posted by JET

What is the white thing on the valve cover line, a catch can?

Its not the size that counts! its how you use it!

I am using this catchcan because you can see through it, if (when) oil starts building up in it, I will know.

A more permanent solution is going to be putting a larger catch can there. This will require moving the location of the catch can, but it will be in the same location in relation to the routing of the vacuum line

tpunx99GSX · 03-07-2008

umm... i basically just use a tube that goes all the way to the bottom of the engine.... never really had any problems. even boosting 30 psi.

**Kracka** · 03-07-2008

Krank Vents would solve everyone's problem.

http://evo.dejonpowerhouse.com/

Go to the "misc" section and they should be at the top of the page. I ran these on my S2k and they do what they claim to do. They are huge in the S2k community for N/A and boosted guys. On N/A S2k's they generally show a 3whp gain and on a turbo S2k they have shown up to 20 whp. They also eliminate oil consumption; I went from using a quart every 2k miles (normal for the F20C engine) to using ZERO in my 5k oil change intervals.

Pushit2.0 · 03-07-2008

Did you put a Vac gauge on the crank case to show a difference?

~John

**Kracka** · 03-07-2008

Quote:

Originally Posted by Pushit2.0

Did you put a Vac gauge on the crank case to show a difference?

~John

Who are you asking?

iceminion · 03-07-2008

I have not measured how much vacuum the thing creates, ill do it because I am curious.

That "Krank vent" is just an upgraded PCV valve. It does not deal with added pressure in the crank case, just look at the picture! and its $110 plus shipping!

**JET** · 03-07-2008

Does it not connect to the same place as yours?

**Kracka** · 03-08-2008

Quote:

Originally Posted by iceminion

That "Krank vent" is just an upgraded PCV valve. It does not deal with added pressure in the crank case, just look at the picture! and its $110 plus shipping!

The KV's create a vacuum in the crankcase (even at idle). Does the air "woosh" into the crankcase when you pop your dipstick? It does with the KV's. The KV's are one-way valves similar to a PCV, but unlike factory PCV's they do not leak boost into the crankcase. You put one between the intake manifold and the factory PCV and one on the valve cover breather allowing air to only escape but never enter. Doing this increases engine efficiency by reducing drag on the crank/pistons (more power, better MPG) and also helps the piston rings seal better reducing oil consumption. These will also fix symptoms such as leaking gaskets and dipstick pop-out similar to your pump.

Pushit2.0 · 03-08-2008

Quote:

Originally Posted by Kracka

Who are you asking?

You and Iceminion, It would be nice to know the before and after with both setups.

~John

**Kracka** · 03-08-2008

Quote:

Originally Posted by Pushit2.0

You and Iceminion, It would be nice to know the before and after with both setups.

~John

I do not know how much exact vacuum is made, but I will say that at even just idle the oil dipstick is suctioned in and takes some force to pull out, and when it is pulled out you can hear the air rushing in.