Sorry, just kidding...

Since I haven't run any of the tests myself, here's what I believe will occur: (Warning: theory & conjecture follow. While data evaluation will follow accepted practices, no claims are made to the validity of any comments, observations or opinions.)

Sorry, where was I? Oh yeah: as your boost pressure increases, it may overrun the spring's force against the piston, causing boost to leak past the piston & recirculate back into the airbox for another try at getting into your engine. Loopy, huh? Anyhoo, you should see this on your gauge as a loss of boost, similar to what happens when the Bosch's diaphragm develops a hole & the same air-loop-thingy happens. Full loss? Partial loss? Dunno. I guess that depends on how much the spring gets overrun. Haven't tested it. See that "Warning" thing up there?

The good news is, if you suspect a weak spring, you can test it yourself with a hand/bike pump that has a gauge. The guy on the B5 site has a picture of how to set up the valve using a cut-apart bicycle inner tube & a gear clamp. Although he does warn that "This is NOT a real life simulation," (read that "Warning" thing again) it's good enough to tell if your valve leaks from the boost-pressure side, & at approximately what pressure. Remember, unless your pump has been calibrated to a known standard, it's only "sorta close." I did email the guy & I asked him about testing my Bosch valve. Besides telling me how to make it "honk like a duck" (which made me vaguely uncomfortable for a variety of personal reasons), he feels the vacuum pump method is more accurate, since you can actually read how much force it takes to move the spring from the vacuum side. Seems logical enough to me. But, y'know, what's THAT worth?

On the plus-side of things, my wife has stopped calling me "anal" & has instead started calling me "linear." Now if I can only figger out how to get her to call me "Aero"...

posted by 32.103.218...

• question about BPV springs, Jason 0W-40, Fri, 22 Nov 2002 20:59:07
  • Thanks for the explanations guys--Dean, about your idea, Jason 0W-40, Sat, 23 Nov 2002 23:32:45
    • So are you running yours backwards too?, Greg Netzner, Sun, 24 Nov 2002 02:55:34
      • Re: So are you running yours backwards too?, Jason 0W-40, Sun, 24 Nov 2002 14:37:09
  • Yowza! How 'bout an "Oil Poetry" question instead?, Greg Netzner, Sat, 23 Nov 2002 02:29:00 <-- Viewing This Message
    • BPV basics.... LONG, Dean, Sat, 23 Nov 2002 12:38:34
      • Re: <--- what he said..., Simon S, Sat, 23 Nov 2002 13:06:02
  • If it breaks you will know your car will not..., Mohammd, Sat, 23 Nov 2002 00:20:43
    • Re: If it breaks you will know your car will not..., Dean, Sat, 23 Nov 2002 12:41:03

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