# What is biturbo?



## MontyCrabApple (Feb 11, 2003)

Looking at the Audi site I notice the A6 2.7T is biturboed. My question is, is biturbo just a fancy way Audi says twin turbo or is it different from twin turbos?

________________________________________________

"Aww! I dropped my peanut." "Where is that little..." "Aww. A twenty dollar bill! Psssh! I wanted my peanut."
*Wait you fool, that twenty dollar bill can buy you MORE peanuts!*
"Explain how?"
*Money can be exchanged for goods and services.*
"WOOHOO!" 
"Oh, no! The money flew out the window!"
"Aww. I wish I had my peanut."

- Homer Simpson


----------



## dave_f (Dec 11, 2002)

biturbo= twin turbo
just like bicycle = two wheels


----------



## holy200sx (Jan 8, 2003)

the A6 is a V6 if i am not mistaken, and i believe bi-turbo would actually mean 3 cylandars, (Ie right side) would be hooked up to a turbo, and the other 3 cylandars would be hooked up to the left side, and it would be a bi turbo engine.. i think


----------



## rcsmith (Nov 2, 2011)

*What Bi-turbo really is...*

Actually Dave_F and holy200sx, you are both incorrect.

Biturbo is the same as "Sequential Twin Turbo"

Basically, you have 1 smaller turbo for lower RPM range, and a larger turbo for higher range. It helps greatly reduce turbo lag due to the smaller turbo can produce boost much earlier than a super single or twin turbo setup can do. At lower RPM, the smaller turbo spools and produces boost - then when you reach a preset RPM or boost level, a staging valve opens and directs air to turbo 2 (large one) and it now produces the boost for the engine. Usually, stage one turbo is turned off, or its boost is sent into the compressor intake of the stage 2 turbo to achieve a higher output pressure.

Do not confuse Biturbo / Sequential Twin Turbo with "Twin Turbo".

Twin turbo is having two EQUAL size turbo's. Each runs off its own cylinder bank in V or H type (boxer) engines, or off of a turbo manifold on inline type engines. Both turbos share the load equally in producing boost air. (Like a dual core processor in your PC - both run at same speed, sharing the load equally) So, turbo lag still effects this type of setup, as both turbos will spool at the same time.


----------

