The Mercedes-AMG GT has been a hit of a sports car, not only for Mercedes-AMG itself, but also for the collection of aftermarket tuners that have since developed kits for the car since it arrived in 2014. You can even make a case that the AMG GT is the most tuned performance car of the past few years, something that well-known tuners like Brabus, Mansory, and Wheelsandmore can attest to. Even tuners that aren’t as well known like Dime Racing have also developed kits for the sports car and now, you can add Luethen Motorsport to that list and its 612-horsepower upgrade for the AMG GT.

It’s true that Luethen is a relative unknown, but don’t let that anonymity fool you into thinking that it’s in over its head because it’s not. A quick look at its website reveals that the German tuner isn’t just known for its Mercedes programs; it also builds kits for BMWs, Audis, and Porsches. That’s a good menu of brands to build up one’s tuning portfolio.

So this kit about the AMG GT is the latest in a line of programs that Luethen Motorsport has built. The engine upgrade sits at the heart of the kit, but it’s also offering a carbon fiber aerodynamic kit and a new set of wheels. In other words, it’s a comprehensive kit that should attract its fair share of AMG GT owners.

Obviously, the tuner faces some stiff competition from other other tuners. But it’s been up to the challenge before with all the past programs it’s built. History dictates then that it’s going to do just fine with this program for the AMG GT.

Continue after the jump to read the full story.

Exterior

Luethen Motorsport provided a unique carbon fiber aerodynamic kit for the AMG GT, one that includes a new front spoiler lip with an integrated splitter and a few winglets. There’s also an adjustable rear wing and an underbody diffuser, providing the necessary downforce the sports car’s going to need if it hopes to maximize the enhancements given to its 4.0-liter twin-turbo V-8 engine. A set of side sills and an underbody diffuser complete the aero kit and a set of the tuner’s own 20-inch, Series-1 forged alloy wheels wrapped in Pilot Super Sport tires rounds out the exterior upgrades.

If this kind of upgrade looks familiar, that’s because other tuners are offering similar body kits to the AMG GT. Take Dime Racing, for instance. It’s not particularly known for being a world famous tuner, but it still provided the AMG GT with its own rear spoiler, and a massive one at that. Other tuners like Brabus, RevoZport and Mansory have also built tuning kits for the Mercedes sports car that includes aero kits as one of the focal points of their programs. RevoZport, in particular, is even offering carbon Kevlar as the material for its aero kit.

Interior

There are no interior upgrades to speak of on Luther Motorsport’s program. Normally, that doesn’t really take away from the overall product, and it’s especially true in the case of the AMG GT, since tuners like RevoZport and Dime Racing also paid no attention to the sports car’s cabin. But there are still exceptions like Brabus and Mansory. These two tuners are famous for a reason and a big part of their reputations is tied into their penchant for covering all the bases with their aftermarket kits. Take Brabus for example. It doesn’t have a comprehensive checklist of upgrades, but the illuminated Brabus-branded carbon-fiber door sills, matte-anodised pedals, and aluminum paddle shifters are enough to potentially convince a customer to for its kit rather than one that ignores a car’s interior entirely.

Drivetrain

Leuthen Motorsport didn’t expound its engine upgrade for the AMG-GT, leading me to think that it only opted to make software modifications to the V-8’s engine control unit. The output results from the kit - 612 horsepower and 576 pound-feet of torque - is what you’d expect from a program of this nature since other tuners with similar results reached around the same levels of increase with their own engine kits. Brabus, for example, was able to get 600 horsepower and 553 pound-feet of torque from its remapped ECU while RevoZport managed to get slightly more at 650 horsepower from its own ECU remap, the addition of a free-flow intake system, and a new titanium exhaust.

Other tuners like Mansory and Dime Racing, however, have managed to get more than 700 horsepower out of the AMG-GT’s V-8. Their secret? Larger turbochargers. Mansory managed to squeeze out 730 horsepower out of the V-8 engine while Dime Racing came up with as much as 745 horsepower.

The lesson here is if you want a good enough upgrade to get your AMG-GT’s output up to north of 600 horses, an ECU remap and the addition of a few auxiliary parts should get the job done. But, if you want a full-blown engine upgrade that’s going to give your AMG-GT enough power to compete against today’s supercars, you’re going to have get a tuner that’s prepared to do more than make tweaks to the engine’s ECU unit.

Check out the table below to get better picture of how Leuthen Motorsport’s engine upgrade for the AMG-GT compares to other tuning programs.

Note: *estimate

Pricing

Leuthen Motorsport didn't disclose the pricing figures of its tuning program for the Mercedes-AMG GT. Given the going rate though for similar aftermarket kits, don't expect to get a lot of change if you spend $50,000 on this program.

Competition

Mercedes-AMG GT S 6.3 Startrack by Wheelsandmore

It speaks to how popular the Mercedes-AMG GT and GT S models are that there are actually more programs for the two sports cars than the listed above. This one comes by way of Wheelsandmore and it follows the same formula of giving the AMG GT S software updates and complementary additions to the overall engine makeup. The result is an output of 626 horsepower and 568 pound-feet of torque, enough to propel the coupe from a standstill position to 60 mph in 3.4 seconds to go with a top speed of 200 mph.

Read the full review here.

Mercedes-AMG GT S RSR by Piecha Design

Piecha Design is another tuning company that put in some aftermarket work on the AMG GT S and not surprisingly, it comes with a similar software program. The result here is an output of 612 horsepower and 610 pound-feet of torque, which gives the AMG GT S the ability to sprint from 0 to 60 mph in about 3.4 seconds before hitting a top speed of 205 mph. Notice how fast that is? That’s likely due to the torque numbers, which is highest listed among all tuners I mentioned.

Read the full review here.

Conclusion

With so many options to choose from, it's going to be difficult for Luethen Motorsport to convince people that its tuning kit for the Mercedes-AMG GT is the best of all of them. The truth is, it's not; but that's ok because the tuner, despite not being a household name, has shown that it's fully capable of building a program that can rival those that were produced by industry names like Brabus. That in itself is an accomplishment that Luethen Motorsport should be proud of.