聽過767i嗎? 採用V16引擎...
BMW E32 767i V16 "Goldfish"
In the late 1980s, BMW secretly built an experimental super 7 that was powered by a massive V-16 engine.
The project was the brainchild of Dr. Karlheinz Lange, the engineer who was in charge of BMW’s powertrain department at the time. He enlisted the help of an experienced engineer named Adolf Fischer to bring to life his vision of a 7 dialed up to 11. Fischer was seen as the right man for the job because he had designed the 5.0-liter V-12 found under the hood of the 750i and the 750iL.
Work on the new engine began in July of 1987. Fischer essentially developed an evolution of the 5.0-liter V-12 (called M70 in BMW-speak) that retained the 60-degree V but received four additional cylinders. The block was cast using high-silicon aluminum, and the heads were each fitted with a single chain-driven overhead cam. All told, the V-16 had a displacement of 6,651 cubic centimeters (about 406 cubic inches), and it was nearly a foot longer than the V-12 it was based on.
The engine was tested on a dyno for the first time on December 24, 1987, and the results were downright impressive. It generated 408 horsepower at 5,200 RPM, and 461 pound-feet of torque at 3,900 RPM. In comparison, the 750i’s V-12 was rated at 300 horsepower and 332 pound-feet of torque, and the U.S.-spec E34-series M5 used a 3.5-liter straight-six rated at 256 ponies and 243 pound-feet of twist.
With the 16-cylinder running smooth as silk, BMW began to look for the best way to shoe-horn it between the front fenders of an E32-series 750iL.
“What was immediately obvious was that the engine would not have fitted without a substantial redesign of the car,” explained project manager Hanns-Peter Weisbarth in an interview with Bimmer magazine in August of 2011.
The super 7 was still largely experimental, so BMW went with the simplest solution. The 750iL’s radiator was sent back to the parts bin and replaced by two smaller units that were installed in the trunk, a setup used more than a decade earlier on the IMSA-winning 3.0 CSL. The engineers cut ducts into the rear quarter panels, installed hand-built fiberglass scoops to direct cooling air to the radiators, and fitted the rear fascia with a wide metal grille in order to extract hot air from the trunk. The custom grille required the use of smaller taillamps, and the license plate had to be relocated to the bottom of the rear bumper. The prototype was painted in a dark shade of gold, so it was affectionately nicknamed Goldfish.
The series-produced 750iL was equipped with a four-speed automatic transmission built by ZF, but the V16-powered prototype used a six-speed manual gearbox borrowed from the 8 Series coupe. It accelerated from zero to 60 MPH in about six seconds, and it didn’t stop until it hit roughly 175 MPH, a dream come true for executives who commuted on Germany’s famed autobahn. The downside is that fuel economy checked in at 11 MPG in stop-and-go city driving, 16 MPG at 75 MPH, and as low as 9.6 MPG when cruising at triple-digit speeds.
Lange, Fischer, and Weisbarth knew from the very beginning of the project that the Goldfish might not receive the proverbial green light for production. The V-16 engine was promising, and bringing a 767iL to the market would have shown the might of BMW’s research and development department, but the automaker’s board of management decided not to move forward with the development of a super 7 Series because a V-12 was deemed big enough. The Goldfish consequently remained a one-of-a-kind prototype and today remains in BMW’s possession, though not on public display.
📝 by Ronan Glon (hemmings.com)
