At the time I drove the Brabus K8, I also learned that the forthcoming 476-bhp bi-turbo 5.5-liter V12 engine for the S600, CL600 and SL600 has prompted AMG to revise the specification of its supercharged 5.5-liter V8. After making just 100 cars with the 476-bhp engine, the SL55 AMG now has 500 bhp. "So we will increase our K8 to 550 bhp," Gander reported.
The Brabus K8 has so much raw, yet totally refined, power that it seems pointless to own it unless you live in a place where you can use the power. More so because using it is addictive, and the awesome performance is so natural and so effortless, it seems almost churlish not to indulge yourself. An indulgence? No, it is simply one of life's great pleasures.
Kleemann SL500
Scandinavia is not exactly noted for its activity in the automotive world, so when I was recently invited to drive a new SL500 equipped with a supercharger system from Danish Mercedes tuner Kleemann, I was as curious as I was excited.
european car reported on a pair of Kleemann cars in the Dec. 2001 issue, but this was the first time I had driven a Kleemann-modified car, and I did not know what to expect. Approaching the drive with anticipation and an open mind, I came away absolutely stunned by the experience, because this car did exactly what was claimed for it, and more.
A great advantage is that the invitation came from Holger Mohr, owner of Kleemann's new German importer, based in Bruggen, on the German border with Holland. We say that because, of course, most of Germany's autobahnen have no speed limits, whereas Danish roads do. And from what I hear, the Danish police lack a sense of humor.
The compact supercharger is made for Kleemann by Swedish AutoRotor, and is a twin-screw positive displacement unit with low internal friction.
The secret is cool air and low boost. Thermal stress puts a limit on reliability, so Kleemann approached heat as the root of all problems. Once you have too much heat at the air intake, you have a cascade effect throughout the whole engine. Then you need a lower compression ratio to avoid detonation, but this blunts throttle response. Then you have to run higher boost to get the power and torque, but the higher the boost, the more heat you get and the closer you run to detonation. It all goes round in a circle.
Kleemann set out to develop a special intercooler system that would effectively reduce the temperature from the supercharger from 100C to no more than 25- or 30C above ambient air temperature at the inlet manifold. This allows the stock compression ratio to be retained, cutting out a lot of expensive internal engine work. It also means that the conversion is easily reversible should you decide to sell the car in standard form.
The innovative intercooler comes from Laminova, another Swedish engineering firm. It is so efficient that at full power it can dissipate nearly twice as much heat from the charge air as the comparable AMG unit. Laminova claims net horsepower gain is higher and is achieved on lower boost pressure. In fact, the other reason the stock compression ratio can be retained is that the Kleemann car uses just 0.45 bar of boost compared to 0.8 bar on the 476-bhp SL55 AMG.
On the SL500 the 5.0-liter V8 goes from 306 bh48% torque increase!
The Kleemann SL50 K starts and drives around town with a 5.0-liter normally aspirated V12 up front.
There is no supercharger whine to speak of, and throttle response is instantaneous, the boosted motor revving sweetly to the redline in each gear, aided and abetted by that strong column of air in the induction. The M-B V8 is a very smooth engine, but it somehow seems smoother still with the supercharger on top.
Where the power of the stock engine peaks at 5600 rpm and gently falls away, the Kleemann motor charges past 6000 rpm smoothly and with real vigor in every gear. Even at well over 250 km/h, acceleration is strong, and the car does not take long to top 300 km/h.
I drive dozens of modified cars every year, many of which are very good indeed. I approached the Kleemann concept with an open mind and was rewarded with a result that stacks up against the very best anywhere. Without pulling any punches, it is one of the best aftermarket supercharger installations I have ever driven.