Turbo vs. Supercharger.

[rocco16v at netzero.net (L F)]

Yeah, Eric, they are making turbos better and better all the time.  
Now, that infinitely variable supercharger drive is a darn good idea.  It could use barometric pressure to control the drive ratio and.....
Let me work on that.....

Larry
sandiego16v
  ----- Original Message ----- 
  From: Eric S 
  To: L F ; scirocco81@vwmail.net ; dale witt ; Neal Tovsen ; Scirocco List 
  Sent: Wednesday, July 02, 2003 9:45 AM
  Subject: Re: Turbo vs. Supercharger.


  Great, so every time I change altitude I have to change the drive pully on the super?  No thanks, thats stupid...rather have something that compensates on its own!

  As for wastegate control, yes, I am familiar with turbo design.  Now Larry, have you seen the latest VNT turbos?  No wastegate...quite interesting design actually...all the TDI engines in the Beetles and Golf/Jettas after 99.5 use a VNT-15 turbo, which is called a "variable vane" turbo....I'm not completely sure exactly how it works, but from what I have been told there is a nozzle of sorts that is constantly varying how much exhaust flows into the turbo.

  Well, I'll tell you, turbo lag on these really dosen't exist...the VNT-15 on the TDI engine is at full boost by the time you hit 1700 rpm or so...basically almost right off idle.

  Here, I found a link, this guy describes it as actually the vanes themselves being adjustable....I'd still like to find a really nice technical design drawing of one of these...but this guys description helps...and he too explains that the turbo has almost no lag...

  http://www.houlster.com/amigo/turbo2/

  So, Larry, till I see some sort of "infinately variable, automatic transmission" for a Supercharger to spin it at different rates depending on conditions....I'll stick to turbos...especially those VNT types...quite a good little design.  

  --
  Eric