MitsuStyle - View Single Post

Andrew7dg · 03-11-2008

I am still confused on how a KV works under boost with a filter at one end...

The KVs are way too expensive. I bought a pack of 6 plastic one way valves for 1.95 that do the same thing and are good for over 100psi (enough for my turbo) hook them up like the KV in the picture and you are good to go, exept hook one end to the intake tube rather then a filter...

I get how the Venturi vucuum pump works however I question how much air it actually moves out. How much PSI have you ran on the turbo with this thing? I would think this would act as a restrictor more then a vacuum in the line.

One thing to consider is that there is a lot of blow by at a higher psi generated from the gasses expanding, not just from intake pressure from turbo. You probably new that already... but know that you need to move lots of air out of the breather valve.

However, looking at the small brass venturi pump in the picture (and the picture is kind of hard to see), it looks like you had to decrease the opening of the breather opening at the venturi pump to get the venturi pump to work...

The air that you are using to flow passed the breather opening (creating the vacuum from what I understand) is coming from the TB vacuum line.

IMO, I don't think that little vacuum from the TB line flows enough air to create the desired effect that you want. You will need a bigger line with more air flow to create the vacuum effect that you want.

But this is just my opinion. If it works, great but I would like to know the dementions of that device.

The idea is there but is the math and proper dimentions?

03-11-2008	#51
Andrew7dg Built it from scratch! Join Date: Mar 2006 Location: St. Paul Drives: Currently Mitsu-less Posts: 851	Re: Venturi vacuum pump I am still confused on how a KV works under boost with a filter at one end... The KVs are way too expensive. I bought a pack of 6 plastic one way valves for 1.95 that do the same thing and are good for over 100psi (enough for my turbo) hook them up like the KV in the picture and you are good to go, exept hook one end to the intake tube rather then a filter... I get how the Venturi vucuum pump works however I question how much air it actually moves out. How much PSI have you ran on the turbo with this thing? I would think this would act as a restrictor more then a vacuum in the line. One thing to consider is that there is a lot of blow by at a higher psi generated from the gasses expanding, not just from intake pressure from turbo. You probably new that already... but know that you need to move lots of air out of the breather valve. However, looking at the small brass venturi pump in the picture (and the picture is kind of hard to see), it looks like you had to decrease the opening of the breather opening at the venturi pump to get the venturi pump to work... The air that you are using to flow passed the breather opening (creating the vacuum from what I understand) is coming from the TB vacuum line. IMO, I don't think that little vacuum from the TB line flows enough air to create the desired effect that you want. You will need a bigger line with more air flow to create the vacuum effect that you want. But this is just my opinion. If it works, great but I would like to know the dementions of that device. The idea is there but is the math and proper dimentions? __________________ "A turbo, exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster."