Sorry for being a noobwad but I don’t actually know what a biturbo is can some one tell me please.
Biturbo is exactly the same thing as Twin Turbo - 2 turbochargers on one engine, in short.
Oh probably should’ve been able to work that out really shouldn’t I.
please read - en.wikipedia.org/wiki/Biturbo
Thank you very much this will make for good reading.
A Biturbo is the same as a twin but one turbo is bigger then the next. One small and one big, the small one for low rpm and the bigger one for high rpm and hi boost.
The size of the turbos doesn’t matter, Bi means 2, thats all.
The Alpina Bi-Turbo had identical turbos.
I always thought biturbo just meant it swung both ways, if you know what I mean 
Twin turbo is two identical turbos on each bank. Biturbo is two inline turbos, usually a smaller one for low rpm and a bigger one for higher rpm.
I’m not sure how effective a straight turbo would be…
[quote=“OCAdam”]
I’m not sure how effective a straight turbo would be…[/quote]
Don’t get me started about those crazy transturbo. 
Read the Wikipedia link above. What you are describing is SEQUENTIONAL turbos, NOT Bi-turbo.
Bi-turbo, twin turbo, is the same thing. Two turbos on one engine.