At more than sixteen feet long and weighing nearly five-thousand pounds the W215 series Mercedes-Benz CL coupes were always going to have more in common with marine mammals than they were with sporty little two-seaters like the Chevy Corvette or Porsche Turbo. At least, that’s how it seemed before 2003, when Mercedes gave the big CL a 493 HP twin-turbocharged V12 engine that blasted the two-and-a-half ton land whale from 0-60 in 4.8 seconds on the way to a 13.5 second ¼ mile time … which, you know, is fine.

What if you want more than “fine”, though?

What if you want your big, comfortable Mercedes-Benz to run down anything on four wheels? What if you want to have your cake and eat it, too? What if, in other words, you want a car that’s less of a marine mammal, and more of a mythological sea monster?

Now, what if you want to do all that and still drive a car that’s emissions-friendly?

Granted, it’s not 2003 anymore and new-car buyers have a few solid options. You could opt for a ludicrously fast Tesla Model S or a Porsche Panamera Hybrid, of course- but what if you’re looking for something a little bit more powerful, and a little bit more “already yours”?

If that’s what you’re looking for, allow me to introduce you to Bobby, and his menacing leviathan of a car. Built by Speedriven in Palatine, IL, this E85-fueled 2003 Mercedes-Benz CL600 is packing more twice the horsepower it came from the factory with, and is ready to blast across the quarter mile line in under eleven seconds- making it more than a match for just about anything on four wheels.

“You could go out and replicate this car, just like it is, for sixty, maybe seventy thousand dollars,” says Bobby, the car’s owner. “You can buy a clean V12 Mercedes for twenty or twenty-five thousand, today” he explains. “Then you have the guys like me that bought it when it was new, or nearly new, and made big payments on it for a lot of years. The car is worth more to me than what I can sell it for, so I’m gonna keep it, and maybe I’m gonna do some work to it to make it feel new to me, you know?”

Doing “some work” to this particular Mercedes CL600 meant sending the car to Speedriven in Palatine, IL- and that’s where SD’s experts in massaging more power and performance out of Mercedes’ V12 engines, began transforming the CL into the 1000 HP, ethanol-fueled street beast you see here.

[insert pregnant pause here]

Before we go further, I think it’s time for a bit of a confession: Speedriven is my day job.

That’s right. Along with a few other dedicated guys, I spend my 9-5 hours (sometimes 9-9 hours) in the somewhat frivolous pursuit of more horsepower and more speed. Long-time readers will, of course, remember the CNG roadster we worked on and the other alt. fuel projects- from Porsches to Nissans– we’ve been a part of in the past, but it’s worth mentioning that I am a bit biased in my portrayal of these cars as awesome, yet somewhat environmentally responsible speed machines. Biased or not, however, the stopwatch- or, the dyno, in this case- doesn’t lie.


This is Some Serious Power


How did we get from 493 HP (about 400 at the wheels) to nearly a thousand? The first step was ditching the tiny turbos the V12 was fitted with from the factory. They were replaced with a set of upgraded turbos modified with Speedriven-specific wheels and housings. Those new turbos are fitted to 3″ stainless steel downpipes and freer-flowing turbo-back exhaust system, as well. Feeding the SD turbos are a pair of massive, anaconda-sized cold air intakes pushing air to a set of top-mounted water-to-air intercoolers. Those coolers work to keep intake temperatures low, maximizing the amount of oxygen reaching the cylinders and burning the ethanol fuel.

The Speedriven hardware and ethanol-friendly fuel system are managed by the factory Mercedes ECU running SD’s own in-house software. So equipped and with a tank full of fresh Ignite Racing high-performance E85, this Mercedes CL600 generates nearly 1000 horsepower at the crank – more than enough, in other words, to make the car feel like new again.

“These are the true supercars,” says Bobby, looking at the results of his E85 fueled Mercedes’ dyno run, above, which shows less of a torque curve and more of a torque mountain. “There’s nothing out there like this, right now, at any price.”


1000 HP E85 Speedriven Mercedes-Benz CL600

Sources | Images: Speedriven and Ignite Racing Fuels, via Motor 1.