Billed as the world’s fastest Mercedes-powered Mercedes, this video shows a RENNtech-tuned Mercedes SLR McLaren doing a 10.31 in the quarter mile. With a trap speed of 136 mph, it’s pretty quick, considering that the mods done to it consisted only of bolt-ons. Combining a smaller supercharger pulley, upgraded intercoolers, revised ECU and a sports exhaust resulted in an output of 770 horsepower. As you can see, the tuner left well enough alone but even with these relatively minor mods, the resulting performance was enough to turn in a pretty quick time.

Publicizing performance numbers of your modified cars is part of the tuning game, as it entices would-be customers towards particular products or vehicles that capture the public’s attention. True to form, RENNtech has trumpeted its quarter-mile time of 10.27 seconds as an achievement to which it is claiming the title of being the world’s fastest Mercedes.

This quarter-mile time, together with a trap speed of 137.46 mph was hit on April 1 of this year at the Palm Beach International Raceway. The CL65’s previous time of 10.51 seconds had been bested by a nitrous-powered C63 and so RENNtech set about to rectify this situation by having its engineers find the extra power necessary to shave more time off the CL65’s already fast 10.5. Mods include a race only tune, upgraded transmission internals and a prototype torque converter. The previous modifications like upgraded ECU/TCU, carbon airbox, limited slip differential, high flow exhaust, drag radials, modified heat exchanger and intercooler pump were retained. Additional lightweight components were used to make the power-to-weight ratio more favorable. According to the tuner, “RENNtech looks to continue shattering its own records and will be further modifying the CL in search even more performance in pursuit of the first 9 second Mercedes Benz.”

RENNtech, one of the premiere Mercedes-Benz tuners, had been providing some CLK 63 Black Series one-off carbon fiber aerodynamic add-ons to a select group of people such as Indy Racing driver Tony Kanaan. Now, the company is making these upgrades available to the general public, mainly due to interest and demand from consumers.

The carbon fiber aero add-ons available include the following: a full-carbon fiber front splitter ($2,450) for that aggressive styling up front, increased brake cooling and improved handling via additional downforce; front air ducts ($1,250) that increase air flow to the brakes for better cooling and reduced pad wear and brake fade; a redesigned full-carbon air box ($2,795) with a new carbon vacuum chamber box, optimizes path of airflow and increases volume as well, up to 10hp added; rear diffuser ($3,250) that increases downforce and reduces drag, plus it also redirects air to help the rear differential oil cooler; a carbon DTM adjustable rear wing ($3,350) for improved styling plus increased downforce and stability; and front && rear adjustable camber bushings ($1,250 for front, $954 for rear) for adjustable handling to accommodate a variety of tracks as well as driving styles. The individual parts are available in gloss or matte finish.

As you can see from the prices of those aero upgrade components, there was really a reason why they remained exclusive options until now. Still, one can’t argue with the effort and engineering it took to come up with these carbon fiber upgrades.

Germany’s not the only country with its pool of talented Mercedes-Benz tuners. One of the best MB tuners in America, Renntech, now offers their latest take on the C63 AMG.

They call it the Renntech C74. The modification package includes upgrading the stock 6.2-liter V8 to churn out 605hp and 555lb-ft. This means the quarter mile run will take merely 11.4 seconds, while top speed is pegged at around 204mph. Lots of credits for the power improvement go out to Renntech’s carbon fiber airbox and high performance filter, a custom air inlet panel, 82mm throttle bodies, more aggressive camshafts, ported and polished cylinder heads, ECU with updated software, stainless steel headers,  performance exhaust system, a 100% locking limited slip differential, fully customizable sports suspension system, Renntech’s Stage 3 Performance Braking Kit, and carbon fiber stabilizer bars for both front and rear.

In case you’re scratching your temple on how Renntech came up with the 74 badging, let’s just say that it’s purely based on the width of the rear wheel track, which measures 74 inches. This allowed the rear drive axle to be able to accommodate up to 11-inches of rims and 315 mm tires.

Of course, it wouldn’t be complete without its host of carbon fiber exterior enhancements, not only to make it look meaner but to make it behave a lot better on the road. These consist of carbon fiber rear decklid spoiler, front splitter, rear diffuser with integrated exhaust tips, 3-piece forged aluminum wheels and Nitto INVO performance rubbers.

Price of the performance package? $11,900. Not bad eh?

Ready for a little bit of madness? Some time back, the guys down at Domani Motors were able to get their hands on an SL65 AMG Black Series, and put it in their showroom. However, they weren’t really intent on keeping the car in ‘stock’ form. They felt that the car was capable of even more awesomeness, and so that’s what they did. They perked up the car and made it even more other-worldly than it already is. They did this with the help of their pals down at Renntech, whose Performance Package 1 was just what the doctor ordered to make their dreams come true.

For those of you who are boggled out of your minds, it’s sort of PCP for the Silver Arrows. The teams worked together to remap the ECU, install a more open exhaust system plus a few other neat tricks to manage the impossible. The end result is around 805 horsepower and 1,000 pound per feet of torque. And what’s even more impressive is their brainchild is completely streetable, albeit with a few reminders to whoever is going to drive it. There’ll be cops on the loose, mind you.

If you do end up driving one, might we suggest that you take note of the 100-percent locking rear differential that the guys put into place. It takes all the power the engine can muster and throws it without any consideration to the rear wheels. Remember, this sort of hardware is almost similar to a spool, which is ILLEGAL in most states in the US, by the way. It’s the sort that race cars come equipped with to tear down corners on a race track. The car also comes with an upgraded tranny to comfortably handle the immense power of the engine. Excessive? Not quite. Fun? Undeniably.

The Renntech SL65 Black Series dyno run had 5 more HP than the Brabus Vanish, which was clocked in at 800 HP. That’s also 135 more ponies and 263 more lb-ft than the stock SL 65 Black Series.

This car means business even next to SLRs Roadsters. The SL65 Black Series has the kind of threshold of power-to-weight-to-possible grip. Everybody would surely like to experience this kind of power. It is simply a monster HP/torque kind of vehicle.

The Renntech version gets an ECU revision, upgraded intercooler pumps and sport mufflers in a package that begins at $16,390, which when you look at the price tag of the actual SL65 Black Series at $250,000 is pocket change. That doesn’t include the transmission upgrade and LSD you’ll probably want to go along with it.

Head over to Jalopnik and check out system in more detail.

One of their projects with be the RENNtech 777, or better known as the re-skined and reworked Mercedes SLR. The 777 concept is really an all-new car that makes use of the advanced carbon fiber chassis of the SLR McLaren. It can be described as a street-legal track car. It will run on a revised 5.5L supercharged “Kompressor” v8 engine, with internal and external performance upgrades that will take the car passed 210 mph.

PRESS RELEASE

Lake Park, FL – 15JAN2009 – RENNTECH 777 20th Anniversary, or: Horsepower Wars really Really REALLY Not Over

Earlier this week, AMG boss Volker Mornhinweg announced that “the horsepower war is over.” If this sounds familiar, it’s because AMG issued a similar press release LAST JANUARY.

“Last year, it was a coincidence that we were releasing a new, 695 hp performance package for the 65 series AMG cars at around the same time. We sent out a press release that said ‘HP War Not Over’,” recalls Hartmut Feyhl, president of RENNTECH and four-star General of the horsepower wars. “This year it is the same timing again, and we have something much more extreme to announce for our 20th Anniversary.”

Feyhl founded RENNTECH in 1989, and the company has since established itself as one of the world’s premier tuning firms and the foremost authority on Mercedes-Benz performance tuning. 2009 marks the company’s 20th year in business, and the company intends to celebrate by releasing a small number of extreme, limited edition performance vehicles, beginning with the 777 hp, RENNTECH 777 shown here.

“This 777 concept is really an all-new car that makes use of the advanced carbon fiber chassis of the SLR McLaren. It can be described as a street-legal track car, or something closer to what the enthusiasts were hoping for from the SLR, originally – which is more a successor to the McLaren F1.”

RENNTECH heavily revised the SLR McLaren bodywork and aero package using some of the same technology the company used to develop the the GLK Hybrid Rally Racer for Mercedes-Benz, including advanced CFD software to develop the aerodynamics for improved downforce. Even with the big wing, splitters, and skirts, a top speed in excess of 210 mph is well within reach for the 777.

The 777 is much more than lightweight bodywork, however. The 5.5 L supercharged “Kompressor” v8 engine is heavily revised, with internal and external performance upgrades and a significantly upgraded cooling system.

Getting that power to the ground is the job of a fully redesigned suspension and driveline, with a heavily reinforced transmission sending power to RENNTECH’s revolutionary new limited-slip differential. Built for RENNTECH by Japanese supplier OS Giken, the recently-released differential allows for 100% locking between the drive wheels for unsurpassed mid-corner traction. Aggressive Nitto NT-05 ultra-high performance tires wrapped around extremely lightweight, 1 pc. center-locking wheels round out the street -legal handling package.

“The 777 will be a very special car,” explains Hartmut. “The first example is being built now, and will be ready this Spring. We intend to build a few different extreme vehicles like this for our 20th anniversary, with each one being strictly limited to 20 units. They are all very exciting projects, and we will be announcing them throughout the year, as they approach completion.”

Contact RENNTECH for information and RENNTECH 777 SLR McLaren package pricing.

The competition wasn’t easy, with BLVD Customs’ strong GLK “Urban Whip” roadster and Brabus’ slick “Widestar” each swapping positions with RENNTECH for the lead throughout. At the end of the day, however, Mercedes acknowledged that RENNTECH’s sweeping program of upgrades – which included extensive engine mods, software development, aerodynamic bodywork, suspension and brake upgrades, as well as converting the GLK to hybrid drive – pushed RENNTECH’s GLK 350 Spec.R Pike’s Peak rally racer “over the edge”.