Just got the BMWCar magazine and reading it as i type. The twin turbos are not actually located under the hood. They are under the rear bumper!!, where the rear silencers used to be. The charged air is forced back via a pipe leading along the passenger side of the car, hidden by the sill. Up through the wheelarch, the pipe leads directly to the huge, custom made intercooler which is mounted in the front of the engine bay.
The guy who owns it Ron is a millionaire with a lot of spare cash and seems to have written a blank cheque to get this conversion done. He's owned 75 cars. Power is claimed to be 800bhp. He owns Currency Motors and will build ten cars with the twin turbos for $350,000 each. The problem comes from the oil and electrics being run underneath the car to supply the turbos. But you get over the problem of heat dissipation if they were located under the hood. The engine has been left alone. It took 4 months to crack the electronics and do the remapping. Developing and testing the hardware took 4 months too. Turbo lag problems - no says the owner as the hybrid design minimizes lag and maximizes responsiveness. Transmission has been left alone!!
Their website is
www.currencymotorcars.com
690whp..