2017 BMW Alpina B7 first drive: A better BMW

BMW’s flagship sedan, the 7-Series, has never received the M performance treatment. That’s OK, though, because Alpina is here to fill that void. In fact, the small BMW-exclusive tuner company does such a good job of building what is, in effect, an M7 that we doubt BMW could top it.

Alpina is a company of 230 employees that started out 51 years ago offering a carburetor performance upgrade for the New Series 1500 sedan. The company has worked closely with BMW ever since, and their relationship took the next step in 2002 when BMW began offering an Alpina version of the Z8 roadster. Two years later came the Alpina-tuned 7-Series known as the B7.

CHECK OUT: 2016 BMW 7-Series First Drive

The 2017 model year marks the third generation of B7. Hot on the heels of celebrating its 100th birthday during Monterey Car Week, BMW invited Motor Authority to spend an afternoon with the third-generation B7. After driving it on Central California’s Monterey peninsula and spending some time on the track at Mazda Raceway Laguna Seca, I can say that this is the M7 luxury performance buyers would want.

Building a better BMW

Unlike M cars, the B7 doesn’t aim strictly for performance. Alpina gets a 750i from BMW and modifies it to turn up both the performance and the luxury.

Modifications to the twin-turbocharged 4.4-liter V-8 aim to improve throttle response, low-end torque, and acceleration. To accomplish these goals, Alpina modifies the turbochargers, the air intake system, and the cooling system.

The turbochargers use Alpina-specific compressor housings that provide better airflow, while both the turbocharger housings and the turbine wheels get larger inlet and outlet diameters. Total boost pressure maxes out at 20 psi.

The unique air intake system provides better breathing and lower air intake temperatures. The intercoolers push 70 percent more volume than those of the last B7 and their inlet and outlet manifolds are optimized for flow, cutting pressure losses in half.

All this results in 600 horsepower at 5,750 rpm and 590 pound-feet of torque starting at 3,000 rpm. By comparison, the 750i’s 4.4-liter twin-turbo V-8 makes 445 horsepower and 480 lb-ft of torque, and the more comparable engine in the M5 produces 560 horsepower and 500 lb-ft of torque.

The 8-speed automatic transmission, built by ZF, is upgraded as well with a stronger torque converter, reinforced planetary wheels, more robust cooling, and unique software. Alpina says shifts take just 100 milliseconds and the transmission is optimized for multiple downshifts. It also incorporates a launch control function.

BMW’s new “Carbon Core” structure, which combines high-strength steel, aluminum, and carbon-reinforced plastic to improve body rigidity and reduce weight, acts as a great basis for the B7. Alpina raids the BMW parts bin for all the systems that can make the car handle better, but puts its own spin on things to max out comfort and performance.

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