Here are some spypics of the new Alpina B5 Bi-Turbo. We can se the diffusor with fins as there is on the Alpina B6 S. The engine is surely the same as in the Alpina B7 Bi-Turbo, but who knows, maybe it will have more than 507 Hp. It may be revealed after the 5 Series F10 premiere at Genova.
The other car that is soon going to be officially released is the Alpina B3 S Bi-Turbo with 400 hp, it is going to have a similar diffusor with fines. If not no info on Alpina B7 S Bi-Turbo based on BMW 760i nor Alpina Roadster / Roadster S based on Z4 sDrive35i.