[s-cars] Crank Case Pressure and Turbo Smoke?

[Mark Strangways]

I guess I have a problem, I have no vacuum in my intake between the MAF and Turbo. At 6500 RPM to boot.

I don't know that we are talking about the same thing here.

Mark
  ----- Original Message ----- 
  From: Djdawson2 at aol.com 
  To: strangconst at rogers.com ; cpayne at bconnected.com ; s-car-list at audifans.com 
  Sent: Tuesday, February 22, 2005 12:46 PM
  Subject: Re: [s-cars] Crank Case Pressure and Turbo Smoke?


  In a message dated 2/22/2005 9:05:48 AM Mountain Standard Time, strangconst at rogers.com writes:



    Me thinks me is gonna have to disagree with you on the vacuum in the maf to turbo hose.
      
    If you have a big vacuum there you have trouble.
    What are the restrictors to the air that would create a vacuum.
    No throttle plates, no small diameter hoses, just the MAF and it's screens( if still present)
    The AutoSpeed article should back me up on this.



  You can disagree if you like, but you'll be wrong.  Proof is in the wastegate.  Assuming you're running a stock WG spring, try clamping the hose going to the bottom of the WG.  Go drive your car, and observe your max boost level.  Lower than it used to be, correct?  The only thing that holds your wastegate shut beyond spring pressure is vacuum.  That vacuum comes directly from the MAF to turbo hose, and is uninterrupted by the WGFV, until the computer starts to allow flow from the turbo scroll (boost) which then regulates your boost pressure.

  Trust me, this is the way it works.
  HTH,
  Dave in CO