It's a 1991 Lotec Colani Testa D'oro (Testa D'oro is Italian for Golden Head)
Lotec is the company that makes the Sirius more lately
Only one Testa D'oro was made

price $480 000 USD
engine Ferrari Twin Turbo Flat 12
displacement 4942 cc / 301.6 cu in
bore 82.0 mm / 3.23 in
stroke 78.0 mm / 3.07 in
compression 7.0:1
power 559.3 kw / 750.0 bhp @ 6400 rpm
hp per litre 151.76 bhp per litre
bhp/weight
torque 900.0 nm / 663.8 ft lbs @ 5000 rpm
drive wheels Mid Engine / RWD
weight 1650 kg / 3638 lbs
transmission 5-Speed Manual
top speed 351 kph / 218.1 mph
Lotec Testa D'oro made by Colani + Lotec Racing Team.
In 1991 the Colani Ferrari Lotec Testa d'Oro, with Mike Strasburg at the wheel, hit a world record for vehicles with catalytic converters when tested on Salt Lake, Utah. With a flying start, it achieved a top speed of 351 km/h.
This car was available in 1992 for $500k. It had a Ferrari Twin Turbo Flat 12 wich produced 750 Bhp, developed by Ferdinand Pietz. And was based on a Testarossa
Colani has designed a lot of wild stuff over the years:
1970. Life-size model of a two-part hybrid car. The engine and cam shaft are taken from a Lamborghini Miura, the separate passenger cabin is designed like the cockpit of a glider.
1997/2002. Truck based on a DAF chassis, and Spitzer silo truck on a Mercedes Actros chassis.
Just why the automobile industry never adopted Colani's ideas, which he has propagated for 30 years, and never put the series into mass production will remain one of life's great mysteries.