Last week, BMW revealed the all-new G30 5 Series, the seventh iteration of the marque's E-segment entry. Over at Alpina, a longtime tuning firm of BMW cars, is busy preparing a hotter, more powerful version of the German automaker's latest sedan. Our spies captured the Alpina B5 doing more laps in the Nurburging Nordshleife. Two months ago, our spies also captured the Alpina-tuned 5 Series wagon testing around the same track.

2017 Alpina B5 front 3/4ths

Despite the global debut of the new 5 Series, Alpina still put camouflage on their B5 sedan. Perhaps this is to hide a few of Alpina's touches to the exterior, namely a unique lower front bumper treatment which has been an Alpina signature since the 70's.

2017 Alpina B5 side

Another Alpina signature are the multi-spoke rims which, for this test car, are only being used for the rear wheels. At the rear however, it uses quad exhaust pipes, suggesting that the Alpina B5 may get a different set of tailpipes from the standard BMW 5 Series.

2017 Alpina B5 rear

The G30 also ushered in the M550i xDrive, currently serving as the most powerful 5 Series in the lineup. With the new car's debut, it also paints a clearer picture on what engine will be seen under the hood. Alpina's B5 will use the M550i's engine, internally known as the N63. The N63 is a 4.4 liter, twin-turbocharged V8 engine and, in the M550i, produces 462 PS. With that, expect the Alpina B5 to edge closer to the 650 PS mark as the F10 Alpina B5 is rated at 600 PS.

There will also be a diesel version of the B5, dubbed the D5. The motor in the D5 will be an uprated version of the inline-six in the 530d. For the diesel-powered Alpina, power is estimated at 400 PS.