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Jims5543 Jims5543 is offline
I'm with Bill
 
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Join Date: Feb 2005
Location: Jensen Beach, FL
Posts: 13,028
Quote:
Originally posted by kach22i
My comment was tongue-n-cheek, but I did not know what the sound was.

Thank you for the quick turbo lesson, I just learned something.
I wasn't sure if you were joking or not. I thought everyone knew what a blow off valve was these days with all the tuner imports on the road.

Yes, its a loud and annoying sound but when I am Autocrossing (and on track days) it is necessary.

Once I let my foot off the throttle the the butterflies on my throttle body close it creates a blockage in the flow from the turbo to the engine. This will cause backpressure on the turbo and it will slow down a lot trying to fight the backflow. By releasing the pressure (blow off valve) it lets the turbo spin free until I open the throttle again. Then the BOV will close and the turbo is already spinning at close to full RPM's and ready to give me full boost in a fraction of a second.

So I will gladly take the noise with the performance gain.

Also in the 1st clip the cam corder was mounted on the front hood right next to the BOV on a sticky pod.
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Old 05-23-2007, 04:37 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #30 (permalink)