Noticed one tail pipe on silvy Utube vid and it seemed to me it was screaming at cruise...hard to say. But got to thinking under the influence, maybe like old WWII T2 steamship technology to use LP and HP turbines. HP turbine (really small turbo) gets the bulk moving, but beyond simply stacking turbos maybe there is a vacuum break or electric cutover maybe tied to ECM to redirect the exhaust to LP when the performance demand kicks in (top end) but avoiding having the HP becoming a blockage. Kind of like a transmission for turbos. Make it easier on the AIR PUMP (engine) with the least exhaust obstruction. Different A/R give you optimum performance on different points of the curve give you different economy on different points of the curve. Lot of room under the truck at the back.....wondering about a 4 speed now. And just how does a waste water technology company fit into all this! LOL ....my head hurts. Oh well will be interesting to see real world info instead of investor hype and back seat speculation.

 

bump to see if anybody has anymore info or real world results?