In its stock form, the Mercedes-AMG GT S' 4.0-liter twin-turbo V8 puts out 503 hp. To give the AMG- GT S the power to keep up with the big boys, RENNtech increased performance by an incredible amount. The RENNtech Stage I Turbo Upgrade boosts the AMG GT S' power figure to a whopping 716 hp and 656 lb-ft of torque, all of which goes to the rear wheels. To get this kind of performance, the tuning house added a larger turbocharger, a ECU upgrade, stainless steel downpipes, high-flow air filters and more.

The tuning company also added a full suspension kit that allows for ride height adjustability. Performance figures for the modified sports car have not been released yet, but it's safe to assume that it will be much quicker than a stock model. The performance package isn't exactly cheap at $11,880, while the coilover suspension kit comes in at $1,980. It may be pricey, but we think it's money well spent.