The S-Class remains a popular choice for those in the market for a flagship sedan, so much so that Renntech has built a tuning program specifically tailored for the affluent clientele of the full-sized luxury Mercedes S550.

It’s not a comprehensive kit, but it does include an engine tune that helps the Merc’s 4.7-liter twin-turbocharged V-8 engine increase its output to 530 horsepower and 606 pound-feet of torque. That’s a nice addition to the S550, but it’s far from the only one. Renntech also installed a carbon fiber aerodynamic component to go with a new set of wheels that are only limited to 25 sets. 


Exterior modifications on the Mercedes S550 are light but they do cost the most of the entire kit. On the aerodynamic side, Renntech fitted the luxury sedan with a carbon fiber rear decklid spoiler that the tuner says will fit any S550 from 2014 and later. The spoiler serves the function of improving the flow of air in the back and reinforcing the downforce on the rear axles. The only other upgrade to the exterior is the new set of 21- and 22-inch Deep Monolite 10 Series alloy wheels that Renntech is limiting to just 25 sets.

Renntech’s work on the V-8 only consisted of an ECU upgrade. The method may be straight-forward, but the results are still impressive as the tuner was able to bring the output from the standard 455 horsepower and 516 pound-feet of torque to a tidier 530 ponies and 606 pound-feet of torque.


Performance numbers weren’t released, but with the standard S550 capable of sprinting from 0 to 62 mph in 4.8 seconds, the tuned-up version could cover that same distance in about 4.6 or 4.7 seconds. That’s enough of a difference to be considered noteworthy, especially for a car with this kind of size. On the flip side, top speed is likely to remain at 155 mph since Renntech didn’t mention anything about removing the engine’s Vmax limiter.

Renntech’s whole package costs a little over US$ 15,000. That’s an affordable price for people who already own a Mercedes S550. Breaking the price down reveals that the limited edition wheels account for the biggest chunk of the total price as it sells for US$ 10,880. Meanwhile, the carbon fiber rear decklid spoiler sells for US$ 1,680 while the ECU conversion is priced at US$ 2,740. Do the math and that adds up to US$ 15,300, excluding tax charges, shipping, and installation.