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I'm running the Stock DET blow off valve it is working I've checked but I don't hear it at all....is there a screw I can turn so I can hear it more is there anything I can do? Thanks
 

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Well when the vlave is working properly on the DET you will not here it.

Lets get one thing straight right off the bat... the DET soes not use a blow off valve, instead it is a bypass valve.

The sound a blow off valve makes is the sound of the air escaping out of the intake tract. Because of the way the DET meters or measures the amount of air coming into the engine the air coming out of the bypass valve is redirected back into the intake tract right after the MAF. This is why you don't here anything. If you were hearing something it would mean that air was escaping and that would be bad because it would cause it to run rich.

So because the air is being sent back into the intake you won't hear anything.

Hope that helps.
Rick
 

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Yes, but just because the air is recirculating doesn't mean that you can't hear the bypass valve at all. I am running a stock bypass valve and I hear it open inbetween shifts when I'm boosting. I just don't hear the same type of sound that a BOV makes.
 

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i would NOT recommend venting to atmosphere. ever seen a DSM car with a BOV floor it? notice when he shifts there is i big poof of black smoke coming out of the tailpipe? thats because the flow meter "saw" air coming in that never made it to the engine, but the injectors have no way of knowing this, so they put the fuel in the cylinder to match the air coming in that never did. only get compressor bypass valves, which are blowoff valves that have a hose that you would attach to the exit nozzle bacl into the intake stream before the turbo and after the flow meter.
 

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Why would you want to put a BOV in place of a Bypass valve on a car equipped with a MAF? Well, technically speaking, a BOV and Bypass are pretty much exactly the same thing except the Bypass redirects the air back into the intake tract.

Putting a BOV on our cars will make it run like crap. You do hear the Bypass valve, but really only when you're boosting and then close the throttle quickly. It's kinda like a muted "pesu pesu". Like in Grand Turismo but quieter.
 

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You should replace it with a Recirc valve from a 1st gen turbo Eclips. It bolts rite in and sounds a bit more appealing than the stock DET valve. I got a nice swoosh sound out of mine.
 

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spdracerUT said:
Why would you want to put a BOV in place of a Bypass valve on a car equipped with a MAF? Well, technically speaking, a BOV and Bypass are pretty much exactly the same thing except the Bypass redirects the air back into the intake tract.

Putting a BOV on our cars will make it run like crap. You do hear the Bypass valve, but really only when you're boosting and then close the throttle quickly. It's kinda like a muted "pesu pesu". Like in Grand Turismo but quieter.
How so?? On the part it'll make our cars run like crap...? They are made for that purpose to release the air, correct? if not correct me.
 

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On the sr-20's you have to put the air back into the intake before the compresser. the MAF has already read that air. If you don't it'll fool the ecu and make it run rich when you get off the gas.
 

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there are a few companies that make a blow off valve that you can recirculate. I believe the blitz you can. all you do is screw off the face part of it, and screw on the adapter for the recirc.
 

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Thats true

james vick said:
On the sr-20's you have to put the air back into the intake before the compresser. the MAF has already read that air. If you don't it'll fool the ecu and make it run rich when you get off the gas.
Yea that is tru James, but... I have three friends with Silvias and a friend with a WRX. All venting to the atmosphere and they have no problems. They only run rich for like less than a second. I thinks its no bgi deal really. Ive heard its sometimes better to recirc, but ur car doesnt run poor or anything if u go atomsphere. so...Not sure.
 

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Ive heard its sometimes better to recirc, but ur car doesnt run poor or anything if u go atomsphere. so...Not sure.
well It is better on the engine if you recirc instead of dump. Over time you can contaminate the oil in the crankcase and dilute its effectiveness.

Also as far as performance goes you want to recirc the air so that it will keep the turbo spooled while you are out of the throttle. When you get back on the throotle you have faster boost response.

Some more reasons for you to consider not doing this. If you are dead set on getting some sound you can check out the turbo xs line of blow off valves and see if you could mod one to fit. My roommate has one on his WRX and it allows him to blow off about 50% of the air and recirc the rest. Pretty sure you would have to mod the piping or valve to make it work but if you must do this than that would be the ticket.

Hope that helps.
If ya want a little more in depth explanation of the way the air flows in the system ( filter > maf > turbo > bypass vlave > throttle plate or back between maf and turbo) let me know and i will be glad to detail it for ya and explain what happens.

Rick
 

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Acutally that is one thing I noticed. There was a whole different response when it was recirc, but... I know the whole cycle pretty much. Thats cool man, thnx.
 
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