LAX

I was wondering if anyone could suggest a blow off valve. I know that they do help the life of the turbo and my friend has one it sounds great. What would you guys say the best sounding on is. Thanks a lot

Andy Hedin

....search archives for more info. Bailey and Forge are two manufacturer's you'll read about.

A4by4

I think you have to use a bypass valve like the one from bailey or something similair, because the air has to be vented back into the intake in order for the car to run properly. Check out www.turbo5.com they should have what you are looking for.

Longwolf (Christian)

I am not an engineer, or a good actor, but I have heard that with a BOV, the car will run rich, and that will take a toll on your turbo.

I know of one guy who has a BOV who has had some big turbo problems, and the tech told me it's due to the BOV.

eMKay (BFLO)

It doesn't help anything, it hurts more.

BigDog

unless it fails, then you would want to by another bypass valve. This comes up almost every week here, and it's difficult to stress how bad the idea of a blow off is. Some people here claim their cars run OK with them. In actuality, the car is almost certainly running rich (check long-term fuel trim via VAG tool, it is a moving average so short term rich/lean conditions can't skew it) which will be detrimental in the long run. My personal opinion is that people who use them care more about sound/appearance than performance and so risk their car's health for that. This is fine, just know what you're getting into.

Joe (zyxt)

I have a Forge bypass, and it's great. Nice quality, metal construction. However, Forge recently came out with a blow-off made specifically for the 1.8t. It's said not to cause any problems, nor will it cause the computer to generate any errors.

I've never used the Forge blow-off valve, so I can't vouch for it as far as it making your engine run rich. However, I was very impressed with quality of the Forge bypass that I got, so I imagine their blow-off is of the same quality build.

Check out <a href=http://www.stratmosphere.com>www.stratmosphere.com</a> for info and purchasing of Forge valves. (That's where I got my Forge bypass.) You should ask them their thoughts on the Forge blow-off and if it makes the engine run rich.
-joe

Joe (zyxt)

You are correct that you can wait until the stock bypass starts to fail before you replace it. However, it's my understanding that the stock bypass can't hold the pressure created when "chipping" the car. It can hold the stock pressure, but I believe it maxes out at 10 or 12 psi. (Not sure on that number... can anyone comment?) After that the boost can start leaking through.

While this won't hurt anything, you're just wasting boost. Based on that information (and since I essentially have a Stage 2 kit) I decided to go ahead and replace the bypass sooner rather than later.
-joe

Andy Hedin

The Forge "Rally" blow-off valve will cause your A4 to run rich....& Strat no longer sells them

Sal R.

but then it would become a bypass valve. At least you get the cool sound..muffled...but still sounds cool.