Racing blow off valves

**Michael Plummer** · 02-06-2010, 09:27 PM

Just picked up my car from Dez Racing and one of the things I had them do was add was a racing blow off valve from ProCharger. This is not the version that vents. I noticed while idling and crusing the BOV whistles. I suspect this to be normal but has anyone found a way to get rid of the whistle?

Thanks
Michael Plummer

**Mustang5L5** · 02-06-2010, 10:19 PM

You have a by-pass valve right? Not a Blow-off? So the air is rerouted back into the intake track and not to atmosphere?

Usually the bypass valves pretty much always vent at cruise because the throttle blade just isn't open enough, so the air is always bypassing until you go WOT. As a result, i've often heard that the sound is noticable at idle and cruise. Sounds like a big air leak. Is that what yours sounds like?

**BAD03COBRA** · 02-07-2010, 08:56 AM

get a louder exhaust...done!

**Michael Plummer** · 02-07-2010, 09:28 AM

Originally Posted by Mustang5L5

You have a by-pass valve right? Not a Blow-off? So the air is rerouted back into the intake track and not to atmosphere?

Thats what I said above it does not vent. I upgraded to the race version from ProCharger and it whistles while idling and crusing. The smaller Proflow bypass valve was almost silent. I was just wondering if anyone that has a race bypass valve, does it whistle? Car is loud enough so upgrading to more exhaust noise isn't an option. My neighbors hate me now because of all the noise. But thanks for thereply.

**SmokinStang** · 02-07-2010, 02:36 PM

I was talking today to another member about this....he runs a Turbo who uses a Racing blow off valve.......He doesn't get any whistle. Maybe on backwards (which I highly doubt if Dez installed), or perhaps it's defective. What did Dez say about it?????
SmokinStang

**Michael Plummer** · 02-08-2010, 07:31 PM

Dez said they all do it and I should crank up the stereo. I made an adjustment (opened it up alittle bit more) and it calmed down alot. So I'll leave it at that and see what happens.

Smokinstang, you had a video where you did a walk around on your car. Do you have a racing bypass valve on yours?

**PROTREE** · 03-11-2010, 12:31 PM

the procharger race bypass valves are noisy but work well ........the race bypass vents to atmosphere while not under boost .

**SmokinStang** · 03-11-2010, 11:20 PM

Smokinstang, you had a video where you did a walk around on your car. Do you have a racing bypass valve on yours?

Don't know how I missed this one? No I dont......
SmokinStang

**Michael Plummer** · 03-12-2010, 06:44 AM

Originally Posted by PROTREE

the procharger race bypass valves are noisy but work well ........the race bypass vents to atmosphere while not under boost .

ProCharger selsl 2 race bypass valves. One vents to atomsphere and the other is recirculated (I have this one). I've gotten use to the whistle now, it grew on me.
Thanks for the comments everybody.