While BMW recently introduced the 840i to the US market, this 640i convertible modified by German tuner Senner packs even more power than its 8 Series equivalent. As standard, the F12-generation BMW 640i convertible is powered by a 3.0-liter twin-turbo inline-six engine producing 315 horsepower and 330 lb-ft of torque paired with an eight-speed automatic transmission.

Thanks to some chip-tuning, the modified BMW 6 Series convertible now develops 379 horsepower and 398 lb-ft of torque, which is 58 more hp and 66 more lb-ft than the stock version. It's also more powerful than the larger 840i, which develops 335 hp from the same engine. Senner hasn't said how these modifications affect the 640i's performance, but the extra power should make the convertible quicker off the line than the standard car.

To complement its extra performance, Senner has also made some mechanical and cosmetic modifications. The tuner's BMW 640i convertible is finished in black sapphire metallic and also gets a KW coil-over suspension with adjustable height and variable tension and compression to sharpen up the handling. Senner claims the highlight of the tuning job is the car's eye-catching 9×21-inch front and 10.5×21-inch rear wheels manufactured by MB Design, which feature a fancy satin black star design and polished outer rims.

Additionally, the car's kidney grille has been darkened to match the black sapphire metallic exterior and the tuner has also fitted custom tailpipes and a sports air filter. The soft-top can also be operated using an OE-remote control.

Senner hasn't made any modifications to the interior. The tuner also hasn't said how much the owner paid for the modified BMW 640i convertible. In the US, a stock version will set you back $86,700 for the rear-wheel drive 640i and $89,700 for the all-wheel drive variant. Topping the range is the 650i, which packs a 4.4-liter twin-turbo V8 producing 445 horsepower and 480 lb-ft. Pricing starts at $98,300 for the rear-wheel drive version and $101,300 if you want all-wheel drive.