The first Sportec SPR1 I drove in 2006 was black, and had only rear-wheel drive to deploy its 802 hp. It was the sort of car that you only bring out in good weather, and tuck away again at the slightest hint of a slippery surface.
The Sportec SPR1M (M for Modified) I'm driving today is as white as the driven snow, and with a decent set of winter tires, will happily go anywhere its AWD system will allow, within the limits of its minimal ground clearance. It also has 858 hp.
Unlike many AWD road cars, Porsche's excellent all-wheel-drive system was not designed purely for traction, but rather as a performance-enhancing tool to help you deploy every one of the horses produced by its potent flat-six engines.
Unlike many tuners today who rely more on sales of bolt-ons like wheels, suspension, exhaust systems and chip tuning to boost their bottom line, Sportec is a technically based company that continues pushing the boundaries of what is possible. The engine in the SPR1M is a perfect case in point. Where most tuners would be happy to declare a genuine 800 hp that can be happily pottered around town, Sportec decided there was room for improvement.
The basic SPR1 engine spec is based on the 3.6-liter Porsche GT1 block as the factory Turbo and GT2 and GT3 cars are. With this starting point, the billet steel crankshaft is heat-treated for extra strength and installed in special bearing shells. These were deemed necessary after lubrication problems were encountered during initial dyno testing.
The lightweight pistons are tied to the crank by very light and strong titanium connecting rods from Austrian aerospace and F1 component manufacturer Pankl, which claims they will take 900Nm of thrust at 9000 rpm. The Turbo cylinder heads are gas-flowed and special Sportec camshafts fitted. Early test camshafts had issues because of the extreme loads imposed on a higher-lift camshaft rotating at these extreme revs.
Making over 800 hp requires a lot of fuel and air to be burned, so the bespoke intake manifold has one throttle body per cylinder bank, and two rows of fuel injectors. The second row kicks in at 4500 rpm on full throttle, with the ECU simultaneously cutting back on delivery to the primary set. In this mode, they overlap, each set running below maximum capability so there is still headroom. Three fuel pumps are required to supply this system.
The ECU has a very rigorous protection regime programmed into it and will reduce turbo boost at the slightest hint of trouble. In fact there are two ECUs. The factory Bosch Motronic ME 7.8 looks after the primary injector bank and the ignition, while the Sportec MFC G4.0 is given charge of the secondary injector bank, the electronically controlled throttle bodies, the electronically controlled dampers and traction control.
The evolution engine uses the same basic SPR1-style dual chamber intake plenum with balance pipe and twin throttle bodies. But further work on the flow bench led to revised internal geometry in the intake system while 15 percent smaller ram pipe diameters increase the internal air velocity for a better charge.
Because of this, there was no need to increase the boost pressure, which remains at 1.35 bar, with 1.45 bar on overboost working nicely with the 8.4:1 compression ratio. Overboost is maintained all the time you are on full throttle, rather than the 10 seconds allowed on the stock factory motor. The reason for this is simply one of heat tolerance and flow capacity, which is why Sportec ditched the factory VTG turbochargers for bespoke conventional units. The massive intercoolers, nearly double the thickness of the stock units, are significantly more efficient. The new rear wheel arches are 40mm wider on each side to accommodate them.
"When we came up with the SPR1 concept, it was not our goal to make a 1,000hp car or go for ultimate top speed," Sportec's Uli Hodel explains. "Rather, we wanted to build a genuine 800-hp car that was civilized enough to use every day and also be finished to the highest standards both inside and out. The fact that we now have 858 hp just by improving efficiency is a bonus."
The increased efficiency has also changed the way power is delivered. With its stock 3,600cc capacity unchanged, the SPR1 made peak power at 8200 rpm with the cut-out at 8600. The more efficient SPR1M engine develops 858 hp at just 8020 rpm with the limiter at 8400 rpm in fourth gear and 8200 rpm in fifth and sixth with the stock final drive. Torque is 649 lb-ft at 4800 rpm.
The single-mass flywheel is mated to a beefy dual plate clutch, and the limited-slip differential was changed from the factory GT3 40/60 (acceleration/over-run) ratio to 60/40 for better turn-in. The gearbox internals have been beefed up using steel synchros, and all ratios are stock apart from a taller sixth gear, which runs the car to 395 km/h (245 mph) in still air on the flat. As the 802-hp SPR1 was officially clocked at 378 km/h (234.8 mph) on the banking at Nardo and later unofficially achieved 387 km/h (240 mph) at Papenburg, there's no reason this latest version should not exceed these numbers.
"Top speed is an interesting exercise," says Hodel. "But to be frank, there is no track open to the public where you can test that-and no autobahn straight long enough, either."
You cannot build cars at this level without input from world-class engineers; the company that built the roll cage also makes cages for the Mercedes-AMG DTM racecars. Similarly, one of the two men who designed and made the body components for the SPR1 was also involved with the bodywork for the Porsche GT3. The other is the famous Swiss designer, Franco Sbarro, who made the initial drawings and the performed the prototype modelling.
While the power increase with the trick Sportec engine is truly immense, this doesn't mean that weight loss was unimportant. The target was to trim at least 50kg from the weight of a stock GT3, and in the end the SPR1 tips the scales at 2,965 pounds including air conditioning and stereo.
The new front and rear bumpers, rear wings and rear spoiler are made from carbon fiber. The aluminum doors are the factory items as fitted to the Turbo and GT3 RS. It's always safer to use aluminum rather than carbon doors as they will not shatter upon impact in a crash. The SPR1 Club Sport version has carbon doors because it also has a full roll cage and five-point harnesses for track use.
The result is a car that looks like a normal 997 at first glance, but when you look more closely you realize that the shape and width of the rear quarters are different, while the bumpers and rear wing are also unique.
Satin gray Sportec seven-spoke forged alloy wheels really stand out against the white bodywork. These one-piece 9.0 and 12.5x20-inch wheels weigh just 19.8 and 25.6 pounds respectively, and are sized to fit under the wheel arches perfectly without spacers. The tires are 245/30 and 325/25 Michelin Pilot Sport 2s.
The front and rear suspension is partially Rose-jointed for more direct response, while the Club Sport version is fully Rose-jointed. The Bilstein active damping system, controlled by a Sportec ECU, is unique to this car. Using g-sensors to measure acceleration, braking, yaw, lateral forces and so on, the ECU compares inputs to known values and reacts accordingly.
"We can even program it so that the outside dampers stiffen up as you turn into a corner to reduce roll," says Sportec test driver Andreas Hodel. "Thus we could make the outside damper go stiffer in bounce with the inner going harder in rebound at the same time."
The calculations made by the team suggested that at least 800 hp would be required to overcome the profile drag of the Turbo-width body, and the downforce created by the new front and rear spoilers required to keep the car stable at a V-max beyond 200 mph.
The faster you go, the greater the downforce, and these loadings have to be taken into account when the spring and damper setup is being developed. That in itself is an issue because you want the suspension to be supple at low speeds around town, yet have cast-iron control over body movement at high speeds.
Apart from saving weight and gaining a huge amount of horsepower, every effort was made to save power. To this end, an electric power steering system was used to reduce drag on the engine.
The idea of braking from 240 mph is frightening if you're trying to avoid a obstacles on the autobahn, but in high-speed testing at Nardo or Papenburg, it isn't really an issue as there are no other cars to hit. You go around and around the track and have literally kilometers to stop. Nonetheless, to make sure the car will stop quickly on the road, it comes with the best brakes that will fit behind the Sportec alloy wheels. These include massive 380x34mm ceramic rotors clamped by six-pot calipers in front, and 350x28mm rotors with four-pot calipers at the rear. The factory Porsche PSM system is still there and plumbed in, but Sportec has arranged things in such a way that it can be totally disabled. Then Sportec's own Swiss-made traction control system, adjustable from two to 30 percent, takes over.
Despite the extra power, Sportec is not claiming better acceleration numbers for the M version than the SPR1. Even so, like the top-speed figure accredited by the Nardo officials, the recorded numbers of zero-to-100 km/h in 3.0 seconds, zero-to-200 km/h in 8.6 seconds, and zero-to-300 km/h in 18.9 seconds make this one seriously quick car. But driving the SPR1 around the countryside near the town of Bulach, near Zurich, where Sportec is based, proved that the car is tractable enough to use as a daily driver. The improvement in low-end response over the SPR1 is quite pronounced, and makes the M version a lot easier to drive at low speeds.
Upshifting at 3000 rpm, you'll find its manners now little different from a stock Turbo. Its finely balanced hand-built turbos prove the point that if you build them properly, you don't need VTG turbos for good down-low response. The only proviso in the car's potential as a daily driver is that the race-grade clutch is heavier to use than stock, although this is not really an issue unless you're stuck in a traffic jam.
While it may exhibit civilized manners in normal driving, once you prod this beast, you know you have released a wild animal whose pace is ably assisted by brute force and a following wind.
In full cry, the push in the back is fierce and unrelenting, and although the traction of any 911 is helped by the weight of the engine over the rear wheels, you feel that the AWD system is really earning its keep as the SPR1M slingshots down the road.
On the straight bits between the bends, the car's ability to compress distance is simply awesome, as is the eyeball-popping retardation offered by the brakes.
The suspension is firm, but its secondary ride has a welcome suppleness that keeps things civilized, so you don't end the drive feeling you've gone 10 rounds with Mike Tyson. With so many horses to unleash, this suppleness is absolutely necessary for getting the power to the ground, especially in bumpy corners.
Although the SPR1M does not rev as high as its predecessor, it still takes some mental adjustment to push a 997 Turbo engine past 7500 rpm. But once you've tried it and realize that the revs are still building at 8000 rpm, you just can't get enough of the sound and feel of the flat-six screaming to 8400-rpm redline. The feeling of being warped into another dimension of Porsche driving never before encountered is quite addictive.
I drove the original SPR1 in the South of Spain where you can take liberties with speeding within reason. Unfortunately, the same cannot be said for Sportec's Swiss homeland, where the police are as lacking in humor as Toblerone chocolate is too sweet for my palette. Because of this, I could only use the SPR1M's full power in short bursts when I was sure no one in uniform was looking. However, the rate at which the car rocketed to double the speed limit was clearly indicative of its potential.
As a total package, the Sportec SPR1M does what it says on the tin. It looks different enough to attract knowing glances from Porsche enthusiasts, and its combination of low weight and big power put it right up there with the top-ranking supercars from big name manufacturers.
The important thing for those willing to put their names down on the waiting list is that this car is beautifully crafted in all respects as befits the product of a company with official recognition as a manufacturer. In late 2006, the Swiss transport authority granted Sportec manufacturer status, so the company can now put its own chassis and engine numbers on some of the more radically modified cars like the SPR1M.
That official accolade at last gives this small, but very experienced team of designers and engineers the recognition they deserve.
Longitudinal rear engine, all-wheel drive
3.6-liter flat six, dohc, 24-valve. Lightweight pistons and titanium connecting rods, custom turbochargers and intercoolers, intake manifold, ECU and fuel system
Six-speed manual, steel synchros, modified sixth gear ratio, dual-plate clutch, 60/40 limited-slip differential
Bilstein active damping, Sportec damping control unit
Six-piston calipers with 380mm rotors (f), four-piston calipers with 350mm rotors (r)
Wheels And Tires
Sportec alloy, 9.0x20 (f), 12.5x20 (r)Michelin Pilot Sport 2, 245/30 (f), 325/25 (r)
Flared rear fenders, Sportec bumpers, rear wing
Custom Alcantara and leather upholstery, Sportec instruments
Peak Power: 858 hp @ 8020 rpm
Peak Torque: 649 lb-ft @ 4800 rpm
0-62 mph: 3.0 sec.
Top Speed: 245 mph