Ian Kuah reports on a Zonda-rivalling, 850bhp 21st century toy
This is the story of a supercar from a very small German company. It is called the Lotec Sirius and it looks even more futuristic than the Carrera GT and Enzo. In fact if you were to put all three together, the styling of the two big name challengers would appear fussy and contrived next to the super smooth Sirius.
In broad terms, the Sirius takes the rounded, homogenous style that inspired the Porsche 928 of the late 1970s and translates it into a mid-engined 21st century supercar. No surprise then that it looks more like a concept car than a run-of-the-mill supercar.
Because it looks so futuristic in a 2006 context, it's hard to believe that the Lotec Sirius was actually conceived in 1992, when the world was still hung over from the big late 1980s recession. That is how far ahead of its time this design was then.
The man behind the Sirius is Kurt Lotterschmid, a man with a passion for fast cars and driving. Kurt’s personal racing and hillclimb career spanned the years 1969 to 1984, and culminated in his 1983 German Group C2 Championship title.
That it was only finally finished and driveable in early 2004 was simply down to money, or lack of it. Kurt would have finished the car in 1995 if cashflow had allowed, but this prototype cost him a lot of hard cash that he did not have at the time.
Design and materials
The Sirius is built around a carbon-fibre tub with tubular steel front and rear subframes, off which the powertrain and suspension are hung. The body panels are carbon-fibre, and both front and rear clamshells are hinged to open forwards, while the doors open upwards Lamborghini fashion.
Fundamental to its unique look is the huge area of very expensive bespoke flush fitting wrap-around glass that is the key to the car’s light and airy feel. The triple headlight arrangement predates the Alfa Romeo Brera’s similar arrangement of by a decade.
As you would imagine of a car built to challenge the 250mph barrier, the Sirius has plenty of wind-tunnel work behind it. The nose and flat bottom are designed for ground effect and there is positive downforce over the front axle. The tunnels at the rear have aerofoils made from carbon-fibre, and along with the rear wing, these create significant downforce.
Plenty of motivation
With his racing background, Kurt believes in low weight and big power. So the 1,390kg Sirius uses a twin-turbo version of the robust 48-valve 5,987cc Mercedes V12 -- as used in the Pagani Zonda.
With twin KKK K27 turbos, the Porsche tuner's favourite, set to boost at 0.85 bar, it makes a thundering 850bhp at 6,000rpm with a tarmac rippling 1,000Nm (738 lb ft) of torque at 3,800rpm. This is transmitted to the rear wheels through the same six-speed manual CIMA gearbox used by Ascari, Koenigsegg and Pagani, sitting behind the engine racecar style, with its own oil cooler. The transmission package includes a limited slip differential, while electronic traction control provides a welcome safety net.
Suspension is by race-style unequal length double wishbones with inboard coil-overs, Koni dampers and anti-roll bars. The huge race grade cross-drilled ventilated discs are clamped by big four-pot calipers with servo-assistance and ABS. 255/35ZR19 and 345/30ZR19 Michelin Pilot Sport tyres on very light Japanese-made 9.5J and 12.5J x 19-inch WORK forged alloy wheels provide amazing levels of grip.
Driving the beast
We did not have the chance to test top speed on the day, but the acceleration is definitely in the ‘kicked by a very large horse’ league. The lowered compression ratio loses some of the V12’s initial crispness, but the big block motor has significant inherent torque and the car is relatively light. If you are anywhere in the wide power band between 1,500 and 6,000rpm, all you need do is squeeze the throttle, and irrespective of which gear you are in, strong forward motion is a no-brainer.
In full battle cry the Sirius soundtrack is an amazing cacophony of V12 howl, thrashing timing chains and gargling induction, with the occasional soft flutter of the waste-gates dumping excess boost. It took me a few minutes to work this one out, but then all the lights went on and I pinned down the big V12’s hard-core soundtrack to the same underlying baritone note as the Ferrari Daytona, except that here the thunder and fury comes from behind your head.
The gearshift is not the best money can buy and that is a CIMA issue rather than a Lotec one. The gate is quite close and spring loading towards the three-four plane is not as strong as you might expect. Because of this, you have to be deliberate and precise when you are hunting for a particular ratio across the gate.
Porsche standards of powered rack and pinion steering feel, neutral handling and staggering brakes to match its performance quickly impress, and the Sirius even rides surprisingly well on country roads. The only things to watch are the ground clearance on ramps and the cars sheer width. A 6 ft 8 in wide, the Sirius makes a Diablo feel trim.
Lotec claims 0-62mph in 3.8 sec, 0-124mph in 7.8 sec and a 244mph top speed with the tallest final drive. However, the company has dyno-tested engines in two higher states of tune. “We achieved 1,000bhp with 1,200Nm on 1.0 bar boost, and 1,200bhp with 1,340Nm on 1.2 bar,” Kurt told us.
With limited resources at hand, production would mean a maximum of four cars a year, so the Lotec Sirius is not exactly going to paint its rivals into a corner. However, its stunning futuristic looks and interstellar performance are a loud wakeup call to the big boys.
21st century toy
More so than any contemporary product of the established big name manufacturers, the Lotec Sirius personifies the 21st century supercar that so many of us car enthusiasts dreamed about when we were in school.