I came across this question from one of the Audi forum. One guys asked, why Audi S4 is a "Bi-Turbo", instead of "Twin-Turbo".

The only explanation I can think of is that "Twin-Turbo" uses 2 turbos, usually one is larger then another, spinning at different rev range to eliminate turbo lag, while "Bi-Turbo" uses 2 turbos on each bank of cylinders and spinning simutaniously(spelling??).....

What do you think??

Andy Kuo

------------------

• 1992 Mercedes-Benz 400SE
  
• Pearl Grey/Black Leather
  

ICQ#26950002
Mercedes Owners ICQ ActiveList ID#61730549
Mercedes S-Class Page
http://akry.web.com

I have always thought that different manufacturers call same things(at least the idea is same, there could be slight differencies) with different names like VTEC, Vanos, Variocam etc.

Yes, I have thought that it's just some fancy names given by different auto makers for the same concept of design. However, I peek through S4's engine bay, there's turo on each side of bank, and 2 intercoolers feeding air, while MR2 Twin Turbo uses ONE intercooler on the side, and feeds both turbo. That's how I ended up with my conclusion above....

Andy Kuo

------------------

• 1992 Mercedes-Benz 400SE
  
• Pearl Grey/Black Leather
  

ICQ#26950002
Mercedes Owners ICQ ActiveList ID#61730549
Mercedes S-Class Page
http://akry.web.com

I think that the different name theory applies here. I know that Maserati used the Bi-turbo name as well...

------------------
Benzmac:
Donnie Drummonds
1991 GMC Syclone
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM

Akry, I belive you're right. The Audi A6 2.7T and the Audi S4 both use the 2.7L Bi-Turbo V6. From what I garnered from Audi, each bank of cylinders has it's own turbocharger.

-Nukta

------------------
2000 Volkswagen New Beetle GLS 2.0L, Techno Blue, Gray Leather, Luxury Package, Cold Weather Package, Leather Package, 5-speed, Delivered August 3, 1999
Hakuna Matata!