The Alpina XB7 gets power from a 4.4-liter twin-turbo V8 that's different from the version of the engine in the X7 M50i by adopting larger turbos, different intercoolers, and a revised exhaust. This brings the output to 612 bhp (457 kilowatts) and 590 pound-feet (800 Newton-metrers), versus 523 bhp (390 kW) and 553 pound-feet (750 Nm) for the BMW version.
Gallery: 2021 BMW Alpina XB7
The extra power gets the XB7 to 60 miles per hour (96 kilometres per hour) in a claimed 4.0 seconds, rather than 4.5 seconds of the X7 M50i. The reported quarter-mile time is 12.6 seconds. The top speed is electronically limited to 180 mph (290 kph) or 130 mph (209 kph) if the buyer chooses all-season tyres.
In this video, the XB7 reaches 62 mph (100 kph) in 4.2 seconds. The run from 62 mph to 124 mph (100 kph to 200 kph) requires 10.27 seconds, according to the GPS.
A second run allows for taking the full slate of acceleration times. This time, the XB7 takes 4.48 seconds to reach 62 mph (100 kph). The quarter-mile comes up in 12.33 seconds. Going from 0 to 124 mph (200 kph) requires 14.85 seconds. The half-mile time is 19.36 seconds. The run to 155 mph (250 kph) from a stop takes 27.4 seconds and covering 1 mile requires 31.31 seconds.
The Alpina XB7 retails for £134,300 in the UK. In comparison, an X7 M50i starts at £95,815. European deliveries of the big Alpina crossover begin in September.