[Bowser330]

Borg Warner’s R2S two-stage turbocharging system, which uses high-tech coatings to withstand extreme temperatures and features the company’s variable turbine geometry. This allows the engine which uses it to offer increased torque at low rpm, a higher output at top engine speeds achieving a low fuel consumption returning and improved emissions figures. The turbocharger is a key component for the downsizing process.
http://www.realoem.com/bmw/showparts...63&hg=11&fg=50


http://www.invasionautoproducts.com/bmwcartu531.html
Smaller initial turbo is Borg Warner K26

http://www.invasionautoproducts.com/bmwcartu54.html
The bigger secondary turbo is the Borg Warner K39

I wonder what modifications can be made to the K39's to have them boost a bit more?

[Kamando]

Good find, thanks!

FYI the U.S. 335d has the M57, the N57 is only in Europe (ie 535d).

[GreekboyD]

Are the US 335d turbos from BW too?

[neovb]

From what I found, yes they are.

[Bowser330]

Originally Posted by Kamando

Good find, thanks!

FYI the U.S. 335d has the M57, the N57 is only in Europe (ie 535d).

Thank you for clearing that up for me...

I wonder what can be done to change them from sequintial to true dual , and fit the engine with two K39's or even two larger turbos.

or maybe keep the sequintial turbo setup but just upgrade the larger K39 to something even larger...so the K26 helps spool the larger turbo to eliminate lag but then you get higher peak horsepower form the larger turbo.

[Coolieman1220]

i wonder what BMW is doing with the triple tubro diesel. what size those have.

I knew we had Borg Warner equipment but didn't know which models. That secondary unit is big! no wonder it moves like hell.