The Mercedes-AMG E63 has been the subject of numerous tuning jobs, as has been the case since the four-door saloon was unveiled in 2013. Tuners like Brabus, Wheelsandmore, and Performmaster have taken stabs at building programs for the AMG E63 and most of them have succeeded in their own right. Now it’s the turn of Posaidon, a German tuner that specializes in Mercedes and Maybach vehicles. It may not be as known as Brabus or Wheelsandmore, but Poseidon sure knows how to get one’s attention, thanks in large part to an engine upgrade program that helps raise the car’s output to a silly 1,020 horsepower and 1,032 pound-feet of torque.

Beyond the absurd increase in power, Poseidon’s program, called the RS850+, also has upgrades on the exterior and interior, in addition to modifications to the suspension, and a new set of wheels. There are plenty of details to go by here, but the real interesting part about this kit is the way each section was modified to work in concert with the other sections to create a full-blown tuning experience that might actually be a little better than what a world class tuner like Brabus has to offer.

That’s of course subject to interpretation but nobody can deny that Posaidon’s work on the AMG E63 is the kind of tuning wizardry that turns a high-performance, four-door sedan into a world-beating machine on four wheels. Think that's not the case? Well, 1,020 horsepower coming out of a heavily tuned 5.5-liter bi-turbo V-8 engine would beg to disagree. Oh, and by the way, this program is completely streel-legal. Wow!

Continue after the jump to read the full story.

Exterior

Carbon-fiber makes an appearance in this program as Posaidon used the lightweight material in fixing up a slew of new components for the AMG E63 in the name of making the sedan lighter. The bonnet, in particular, gets a new look with the generous amount of carbon fiber and the presence of inlets, presumably to get more air into the engine. Speaking of increasing airflow into the engine bay, the tuner also took out the AMG E63’s grille and Mercedes logo, replacing it simple wire mesh. The front bumper also gets the carbon fiber treatment, as did the mirror caps, rear spoiler, diffuser, and tailpipe trims. Rounding out the exterior upgrades is a new set of 20-inch wheels ET37 and ET45 ADV.1 alloy wheels. The ET37 wheels are used in the front and are wrapped in 255/30R20 tires while the ET45 wheels are fitted in the rear with 295/25R20 tires.

Interior

Posaidon’s objective to shave as much weight off of the sedan is also evident in the interior with the complete removal of the rear seat and the door panels. While the car still has four doors, the rear section of the cabin contains nothing more than the frame where the seats used to be. Even the front section of the car’s interior was changed, specifically the front seats, which have also been removed in favor of a pair of race-style lightweight wheels from the AMG C63 Black Series model. A Blitzer update on the sedan’s Comand system complete Posaidon’s interior upgrades for the AMG E63.

Drivetrain

Posaidon’s work on the AMG E 63’s 5.5-liter bit-turbo V-8 engine is as extensive as it’s going to get. The whole program starts with the addition of a pair of larger turbochargers and installation of more efficient intercoolers. The German tuner also added a bespoke carbon fiber-encased intake system that incorporates a free-flow air filer to help augment the ram intake car. Posaidon also installed new spark plugs and a handmade turbo-back exhaust system lead to a valve control rear silencer. Once all of that was done, the final piece of the engine tuning puzzle involves the customization of the sedan’s ECU to account for all the changes made to the engine’s hardware.

The result is an incredible 1,020 horsepower and 1,032 pound-feet of torque, enough to propel the AMG E 63 from a standstill position to 62 mph in just 2.8 seconds to go with an electronically limited top speed of 217 mph. Posaidon did post a theoretical top speed of 229 mph, but opted for the safer 217 mph on account of taking care of the tires.

Speaking of compromises, the tuner also uprated the sedan’s seven-speed sports transmission to be able to handle the significant torque numbers. Likewise, specially calibrated limited slip differentials were also installed in the front and rear axles of the car.

Chassis and Suspension

One of the prevailing themes of Posaidon’s RS850+ kit for the AMG E 63 is compromising what it can to account for the massive improvement in power and performance. That also translates into the car’s chassis and suspension with the tuner putting on upgrades in the form of fully adjustable coil-overs and a high-performance carbon-ceramic brake system that makes use of 16.5 x 1.57-inch vented discs clamped by six-pot callipers at the front, and 14.1 x 1.26-inch vented discs with four-pot callipers at the back.

Pricing

There's no word yet on pricing for the RS850+ tuning program. Given the exhaustive work put into this kit by Posaidon, I won't be surprised if the whole program ends up costing more than $200,000, donor car included.

Competition

Mercedes-AMG E63 850 6.0 by Brabus

Brabus’ program for the Mercedes-AMG E 63 was introduced in 2014 and to this day, it still packs a very mean punch. Notable in that kit was the German tuner’s decision to increase the displacement of the engine from 5.5 to 6.0 liters to accommodate the improved output of the sedan. Brabus followed that up by making a few more tweaks to the engine on its way to an increased output of 850 horsepower and 848 pound-feet of torque. It’s still on the light side compared to what Posaidon did, but according to Brabus, the torque figure on the program goes all the way up to 1,068 pound-feet of twist but the decision was made to cap it at 848 pound-feet to prevent the drivetrain from experiencing too much stress. With the modifications in place, the Brabus-tuned E 63 AMG can sprint fro 0 to 60 mph in just 3.1 seconds to go with a top speed of 217 mph.

Read our full review here.

Mercedes-AMG E63 "Seven-11" by Wheelsandmore

Figuring into this discussion of tuning programs for the AMG E 63 is Wheelsandmore’s “Seven 11” kit from December 2015. A lot of work was put into this kit with the most important being the engine tune that saw the German tuner increase the sedan’s output to 700 horsepower and 811 pound-feet of torque. Wheelsandmore achieved that through a concoction of items, including a CRP-F1 kit, a remapped ECU, and a new exhaust system with flap-controlled sports mufflers. The result is a V-8 engine that helps the AMG E 63 sprint from 0-to-60 mph time in 3.3 seconds to go with a new top speed of 190 mph.

Read our full review here.

Competition

This is the beauty of the aftermarket scene in the industry. It doesn’t matter if you’re a famous tuner like Brabus or somebody less known like Posaidon. When you have the chops to build a tuning program, there’s nothing that can stop you from doing it. Posaidon has been in the business for a while now, but this is arguably the most impressive kit we’ve seen the tuner do. There’s a mix of everything here. It’s lighter. It looks more aggressive. And it’s beyond powerful. The only thing I don’t like is the elimination of the rear seats, but I do understand that there was a reason behind it.