Say hello to the unofficial BMW Z4 M, as G-Power likes to call its latest project. The roadster builds on the Z4 M40i spec and gets an impressive power upgrade that unleashes 500 PS (493 hp / 368 kW) and 700 Nm (516 lb-ft) of torque.

The extra 160 PS (158 hp / 118 kW) and 200 Nm (148 lb-ft) of torque (in the Euro-spec) was made possible thanks to upgrades to the 3.0-liter inline-six engine. As part of the process, the firm installed a modified turbocharger, a larger intercooler, a new exhaust system and optimized engine management software.

Also Watch: Would You Take The BMW Z4 M40i, Audi TT S, Or Porsche Boxster GTS?

The 0-100 km/h (0-62 mph) acceleration time has dropped by a few tenths of a second compared to the stock model, which needs 4.5 seconds, although G-Power didn’t say by how much. The top speed limiter has been removed, so the car can now exceed the 300 km/h (186 mph) mark wherever road conditions (and law!) allow it. The v-max increase is a €595 ($678) option.

Speaking about the financial bits, G-Power has put a €1,949.99 ($2,220) price tag on the performance software V3, which is the one responsible for unleashing the full 500 PS. Other mandatory parts are the turbocharger modification (€3,450/$3,929), downpipe with sport catalyst (€1,950.01/$2,221) and larger intercooler (€1,750/$1,993). For an extra €357 ($407), they can also measure the engine output on the dyno, so you’ll know exactly how much power it delivers after the upgrade.

Aside from the boost in power, the tuned Z4 M40i gets new wheels. The 9×20- and 10×20-inch (front/rear) double, five-spoke forged rims, called the G-Power Hurricane RR, are wrapped in 245/30 and 275/30 tires, respectively, and are said to be the lightest in their class.

Lesser power upgrades are also available for the M40i version of the G29 generation, and these will lift the engine output to 380 PS (375 hp / 280 kW), 410 PS (404 hp / 302 kW) or 450 PS (444 hp / 331 kW). The first two kits require an engine software that costs €1,250 ($1,424) and €1,550 ($1,765), respectively, and the latter needs to get the larger intercooler and downpipe with sport catalyst, too, aside from the engine remap, for a total of €5,350 ($6,093), without installation.