Bosch 103 Bypass Valve

[jessetooslow]

can someone tell me why this is a good upgrade over stock. I was looking on 935 motorsports and saw they sell a factory bypass valve upgrade, its the Bosch 103 bypass valve kit, anyone have this kit, whats so special about it?

 

[Larry_A]

It's less expensive than stock.
The Bosch valves function OK, but sound like ass.

 

[jessetooslow]

whats the big deal about it? is it a performance upgrade from stock?

 

[mkIIIman089]

A 103 came on my car from the previous owner, I replaced it with a 110.

Mine works fine, I don't mind the sound at all. It's just a little psssh since its recirculated... whats so bad about that?

 

[jessetooslow]

but is this a performance upgrade, or should I just stick with the factory bypass valve?

 

[MK3Brent]

Everything is a performance upgrade if you're replacing a faulty part.

 

[Poodles]

yep, it will hold more boost, but the cars I've seen with the bosch valves on them all had pretty nasty compressor surge...

I won't run one...

 

[annoyingrob]

I had one on my dad's car, and it leaked (he ran 20psi though). Swapped it out for the heavy duty one (the 110 I think), with a metal reinforced diaphragm, and it holds quite nicely. No surge, and makes a small "Pssh" sound when it opens. Pretty decent for the price IMO.

 

[jessetooslow]

so is this worth buying, or should I just save my money and get a HKS? I won't be running to much boost 13psi the most.

 

[oscolivar1]

Depend if you want function over sound.

If you want the loud whistle or PSSH sound get any of the aftermarket BOV.
The bosch is a good bypass valve. If your completley stock than i would get the Bosch. It sound fine to me.

Either one will be good for you.
Im always up for Function>Sound when it comes to BOV.

 

[3p141592654]

I've used one for a while. Works fine. You also should get the tapered hose mentioned in the link below to get it to look factory.

http://www.cygnusx1.net/Supra/TechTips/porsche_bov.aspx

It is hard to be sure you are getting the right one (model 110) when you actually try to buy the thing since there are models 103, 108, 110 ,114 and so on and on top of that each manufacturer (Saab, Audi, Porsche) have their own part number for the same thing.

I ended up buying the following and it was a genuine 110.

Saab Viggen $49.27 eEuroparts.com CT 4441895 (0280142110) Turbo by-pass valve http://www.eeuroparts.com/productdetail.aspx?code=4849

I think the following are also 110 (or 114 which is basically the same)
Audi 06A145710N
Bosch 0280142110
Porsche PP993.110.337.50
Porsche? C3070-41431
Porsche? C4086-12947

 

[Ckanderson]

check to see if your stock valve is functional. try blowing thru it. If you can, your loosing effecency. I ran one for about 3 months before it failed at 12 psi. I was rather dissapointed.

 

[jessetooslow]

so you guys are basically saying, I am pretty much better off getting one of these Bosch Bypass valves, then getting a expensive one? Is their really a big difference in performance then the high dollar ones, or just louder?

 

[Ckanderson]

i'd save up for a aftermarket one.

 

[3p141592654]

Also depends whether you are designing to pass a visual smog inspection.

 

[TurboStreetCar]

blow off valves dont make your car faster, they make different noises based on the one you buy. you wont see any more power from swapping a blow off valve unless the one your currently using is leaking.