The BMW M4 GTS is more than the range-topping road version of the incredibly popular M4. It also serves as a living testament to the lengths BMW and its M performance division will go through to give its loyal customers a performance car that also doubles as a track-ready coupe. Obviously, a car with the credentials of the M4 GTS will attract its fair share of attention, especially in the tuning world. Look no further than than G-Power to add weight to the M4 GTS’s larger-than-life aura with a tuning program that puts the sports car’s output to an impressive 615 horsepower and 561 pound-feet of torque.
The German tuner was able to squeeze out more power out of the M4 GTS’ twin-turbo, 3.0-liter inline-six courtesy of its Bi-Tronik 2 V3 ECU upgrade. Those familiar with G-Power’s work should be familiar with this tuning module, as the tuner has used it at one point or another on its other BMW programs. The same holds true here as the module once again serves as the foundation of the M4 GTS tuning kit. Having said that, the engine upgrade isn’t the only relevant layer of this particular program. Keeping true to its reputation, G-Power also added a cosmetic touch to the equation by adding a new set of 21-inch wheels, replacing the “standard” versions BMW put into the car.
This program won’t win any awards for being all-encompassing, but for the things that could be improved on the M4 GTS, G-Power put in the work to address those needs. It’s worth noting that while BMW only released 700 units of the M4 GTS. Currently, four of the cars have already been modified with G-Power’s program.
Considering that the BMW M4 GTS already packs plenty of aerodynamic-enhancing details, G-Power smartly left the exterior of the track-ready sports coupe alone, opting instead to keep all the carbon fiber parts that BMW already installed as part of its limited edition nature.
That said, the tuner did replace the stock wheels on the M4 GTS with a new set of 21-inch Hurricane RR forged alloy wheels.
It’s the same story in the interior of the M4 GTS. There are no modifications to speak of coming from G-Power, if for the simple reason that BMW already addressed them.
G-Power’s program for the M4 GTS largely revolves around the engine upgrade program the tuner prepared for the track-ready coupe’s 3.0-liter bi-turbo inline-six engine. At the heart of this modification is the aforementioned Bi-Tronik 2 V3 ECU upgrade, which is responsible for a host of improvements, not the least of which is to ensure that all the hardware upgrades are working in peak condition. These hardware upgrades include larger turbine and compressor wheels, both of which were installed to improve airflow throughout the engine. G-Power also installed new stainless steel downpipes without catalysts to help reduce the back pressure coming out of the engine.
Once the hardware improvements were done, G-Power used the fuel, spark and boost curves provided by the Bi-Tronik 2 V3 module and custom-mapped into the upgrades, helping net an increased output of 615 horsepower and 561 pound-feet of torque. The end result is a sports car that can sprint from 0 to 62 mph in just 3.6 seconds to go with a top speed of 199 mph thanks to the speed limiter being removed.
Those who want a simpler tuning program for their BMW M4 GTS, G-Power is offering its Bi-Troni 2 V2 module with mapping optimization. This upgrade brings the total output up to 575 horsepower and 546 pound-feet of torque.
G-Power didn’t add any chassis and suspension upgrades to the M4 GTS, largely because the M4 GTS already comes with a fully adjustable coilover suspension courtesy of BMW.