Taken from above link for reference...
[ QUOTE ]
My Conclusions/Recommendations:
A DV is a DV. People say they FEEL the difference. I'm more inclined to say that they FORCE themselves to feel a placebo difference because they spent so much darn $$ on a DV! Frankly, if your DV were already bad, and you put in another stock DV, then you're going to feel an overwhelming difference, right? Of course! But if you already have a working DV, and you put another aftermarket DV in there, you really don't feel a difference. At least I didn't.
BLIND TEST: I had a friend install a dv at random in MY CAR. I didn't ask him which one he installed. I then went driving. Came back, and he installed the other one (avg time of 15 mins to install a dv if you know where one is located on the Passat/Audi). went out driving again. Came back, and he installed yet another one. went out, came back. Then I had to decide which one he installed. (yes, I took the same route each time, yes, I tried to keep everything the same). Well, I failed miserably. Frankly, I could not tell the difference. Car performed the same.
Why buy an aftermarket DV? Well, cuz you can clean it and clean it and get a new spring for it and clean it some more! Yes, the spring is a moving part, and you go from vacuum to + boost all the time when you press on the gas. This means the spring is working itself every single time you push on the gas. Well, if this is the case, then a moving part will always wear down, right? Probably. And yes, the LITHIUM grease that you oil it with does get black, why? Because of the dirt and oil that accumulates over time. Will this 'friction' wear down your dv? I supposed so. That's why cleaning it helps because it gives you that new refreshing placebo effect of it being brand new and working better =). It's also nice to buy one of these aftermarket ones because you can always sell it used for $90 or so. That means you only spent about $40.00-$50.00 for it!!!!
Why buy a stock TT one for $35.00? Because I doubt the spring will fail in a month. It's very cheap if you're having boost issues and would like to determine if it is the Diverter valve. It's NOT a weak spring! Look at the results! You can buy 4 of these babies before you get your money's worth on an aftermarket one. I would have to say that one of these will probably last a while. The spring might start to get weaker within a year of use, but I've only test drove mine for 4 months, and so far it's still doing AOK.
Since I don't work for any of these companies nor am I affiliated with any of these companies, I would have to say that any aftermarket dv is nice. I truly liked all of them. Any of the ones tested did well. Metal to me is ALWAYS better than plastic. But if you ever need to take pictures of your mods, please buy an HP digital camera. These things kick butt. Be sure to print them out using an HP printer and HP photo paper, and what compliments the HP printer more than a HP or Compaq laptop (which you can also use for the Vag Com). And be sure to post all your pictures up for us to see at
www.hpphoto.com for free!
[/ QUOTE ]
Kinda what some have been saying all along. The revised Bosch valve is much improved over the A revision and reliable...