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.

As for the rest of the M4 GTS owners, I pose this question: will you be the next?

Continue after the jump to read the full review.

2016 BMW M4 GTS By G-Power

Specifications
  • Make: Array
  • Model: 2016 BMW M4 GTS By G-Power
  • Engine/Motor: inline-6
  • Horsepower: 615
  • Torque: 561
  • [do not use] Vehicle Model: Array
Pros
Cons

Exterior

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.

Interior

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.

Drivetrain

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.

Chassis and Suspension

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.

Pricing

Pricing details for G-Power’s tuning program for the M4 GTS can be seen in the table below:

Item

Price (Euro)

Price (USD)

Engine upgrades

Bi-Tronic 2 V3 module

€3,250

$3,285

Turbocharger modification

€3,650

$6,894

Vmax removal

€668

$760

Downpipes without catalysts

€1,780

$1,946

Wheel upgrades

21-inch HURRICANE RR forged alloy wheels and tires

€7,647

$8,435


Competition

BMW M4 by B&B Automobiltechnik

Ok, so B&B Automobiltechnik’s program isn’t specifically for the M4 GTS, but rather for the lower-rung M4. You can take that as a negative or you can appreciate the work that B&B put into making its own kit stand out. Just like some of the most recent programs for the M4, B&B’s work largely consists of a three-stage performance kit that provides varying levels of power improvements for the sports coupe. Each of the three stages come with modifications to the turbochargers to go with a higher-flow intake tract, larger exhaust downpipes, more efficient charge air cooler, and an ECU remap with revised fuel, spark and boost parameters. The output differs depending on the stage - 490 horsepower for the Stage 1 kit, 540 horsepower for the Stage 2 kit - and none is higher than the Stage 3 kit, which results in an output of 580 horsepower and 553 pound-feet of torque. That’s enough to help propel the M4 from a standstill position to 60 mph in just 3.5 seconds to go with a top speed of 205 mph.

Read our full review here.

BMW M4 by CarbonFiber Dynamics

CarbonFiber Dynamics presented its own program for the BMW M4 and while it incorporated plenty of elements on other parts of the sports coupe, the typical main event of that upgrade was one on the M4’s 3.0-liter bit-turbo six engine. In accomplishing its task, CarbonFiber Dynamics utilized upgraded turbochargers, a new air intake, and a high-flow air filter to go along with a methanol injection kit and a tuning module supplied by Burger Motorsport JB4. The results are as legitimate as they come as CarboFIber Dynamics was able to bring the M4’s output up to an impressive 600 horsepower and 610 pound-feet of torque, good enough to hit a top speed of about 200 mph to go along with a sprint tim of under four seconds.

Read our full review here.

Conclusion

This particular program is impressive not because of what it provides the BMW M4 GTS. Sure, the improvements in power are nice, but this is more about what G-Power is capable of doing, especially when it comes to limited edition BMWs. Remember, the German tuner also built a tuning kit for the M4 GTS's predecessor, the M3 GTS, back in 2010. It shows how capable and trusted G-Power is within BMW's circles and the fact that it's one of the first to have a tuning program for the limited edition M4 GTS speaks to the kind of reputation G-Power boasts of in the tuning world.