The Alpina B10 Bi-Turbo is a high performance version of the BMW 5 Series (E34) executive car manufactured by German automobile manufacturer Alpina. Beginning production in 1989, the B10 Bi-Turbo was based on the 535i and received several upgrades by Alpina, being the fastest production sedan in the world at the time of its introduction. Production ended in 1994 with 507 examples produced.
Developed at a cost of US$3.2 million, the B10 Bi-Turbo was introduced at the Geneva Motor Show in March 1989.
Specifications
To build each B10 Bi-Turbo powerplant, Alpina dismantled a BMW M30 engine, replaced the stock pistons with forged Mahle units, installed two Garrett T25 water-cooled turbochargers, and added a Bosch variable boost control with range of 0.4–0.8 bar, adjustable from the driver's seat. Additional modifications helped raise the horsepower of the standard M30 engine from 155 kW at 5,700 rpm and 305 Nm at 3,000 rpm to 265 kW at 6,000 rpm and 520 Nm at 4,000 rpm. A Getrag 290 5-speed manual transmission was specified to handle the power.
Modifications to the suspension included Alpina-specific springs and anti-roll bars. Bilstein shock absorbers were used at the front and automatic-load levelling units by Fichtel & Sachs were used at the rear. Front brake rotors were large 13.1 in discs from UK-based Lucas Girling, bigger even than the 12.1 in pieces found on the