Being one of the most high-tech cars ever built, Delta S4 had a legendary and dramatic fate. It had actually no relationship with the production Delta series, as you can see from its mid-engined design and tubular space frame chassis. It was designed for pure racing purpose from day one, aiming to beat Peugeot 205T16 and Audi Quattro Sport in Group B world rally championship. It would have done that, if fate was not against it.Although Lancia already had a mid-engined race car called "037" (or "Monte Carlo" for road version), this car was found outpowered (only 325hp, compared with 440hp of Peugoet and 500hp of Audi) and outhandled by rivals (2WD only, unlike Audi and Peugeot's 4WD). Therefore Lancia had to develop the Delta S4 as a replacement.
Like contemporary rivals, Delta S4 was styled and named to promote the mass-production Delta. In fact, under the skin it was a clean sheet design. Being disagreed with Audi Quattro Sport's front-engined theory, it adopted the more popular mid-engined layout. The engine was longitudinally mounted behind the front seats, directly driving the viscous-coupling LSD which transfered 30% torque to front wheels and 70% to the rear. At each of the corners of the steel tubular space frame chassis, double wishbones and twin absorbers were employed as suspensions. All these were covered by a glass-fibre / epoxy resin composite body. (Kevlar for race car)
While its 4WD system was not as advanced as Peugeot 205T16's (which had variable torque split between front and rear axles), its engine was by far advancer. As I know, it was the only car ever employed turbocharger and supercharger simultaneously.
Turbocharger is generally regarded as the most efficient means of forced induction, but it requires higher rev (hence a lot of exhaust gas) to operate. The result is poor low-speed power and the presense of turbo lag. On the contrary, supercharger performs strongly and instantly right from idle, but it is rahter inefficient in high rpm. For a rally car, a flat torque curve over a wide range of rpm is always very crucial, since rally car has to brake to very slow in tight corners and then accelerate to near top speed in 10 seconds. Therefore Lancia spent a lot money with Abarth to develop a system combining both turbocharger and supercharger to get a perfect output. It employed twin intercoolers, one for the turbo and one for the supercharger. The supercharger worked at low speed. Once the turbo cut in, a bypass valve relieved the pressure from the supercharger so that energy efficiency was be lifted.
This system was not only complex, but also faced great difficulties during development. The biggest problem was the transition between supercharging and turbocharging, since a short zero-boost period existed. However, after further developement, this problem was eventually solved.
As a result, the 1.8-litre engine had an outstanding power of 250 hp and a healthy 214 lbft of torque, while the rally car had at least 470 hp and 333 lbft.
Like other Group B cars, only 200 units of road version were made to fulfill the minimum requirement for homologation.
In WRC, Delta S4 experienced a dramatic fate. It won its debut race, then continued to dominate the following races and was leading both the driver and manufacturer championship standings. Such excellent results amazed everyone, since it was a completely new car. In 1986, Tour de Corse (Corsica Rally), leading driver Henri Toivonen and navigator Sergio Cresto crashed in their S4 and both were killed. The team lost its momentum and eventually handed the title to Peugeot. This accident led to the rethink of Group B cars. Races went on but finally FIA annouced the termination of Group B, because it was too powerful and dangerous. Therefore, Delta S4 became the most outstanding rally car in history that did not won world title.
Rocket (1992)
Light Car Company's Rocket rewrote all the golden rules for supercars. It proved that maximum handling and driving fun could be achieved without 500 hp engine, 2-meter wide body and 335 mm rear tyres. A motorcycle engine and a kart-like chassis are what you need.The part-time sports car specialist was founded by former racing driver Chris Craft just in the early 90s, and the Rocket was his first project. By his name, you'll know he is a good craftmen rather than a good car designer, so he hired the famous Gordon Murray to design the car. If you don't know him, listen: Murray is a top Formula One chief designer whose cars won five world championships. After retiring from motor racing, he created the McLaren F1 road car.
Interestingly, the philosophy of Rocket was even more loyal to Formula One than McLaren F1. Not only looked like a Formula racing car - with narrow body, exposed wheels and suspension linkages, open cockpit, no windscreen - its structure was also pure Formula racer-inspired. The engine was used as stressed structure to support the rear suspensions like Formula One, the narrow, cigar-shaped chassis was made of nickel-bronze and constructed as space frame, covered with light alloy inner panels and glass-fiber outer panels.
Power came from a motorcycle engine - Yamaha FZR1000's 1002c.c. straight 4, with 5 valves per cylinder. Like the superbike, maximum power of 143 hp occurred at sky-high 10,500 rpm, and 77 lbft torque at 8,500 rpm. The engine was mated to 5-speed sequential Yamaha gearbox, and then to a special final drive which incorporated limited slip differential (LSD) as well as a reverse gear, since the motorcycle gearbox had no reverse.
As you might predicted, Rocket was extremely light - only 400 kg. This gave it a very good power-to-weight ratio but most important was that the ultra-lightweight optimized handling and braking. As commented by Autocar magazine, Rocket rewrote any experience of driving a sports car with its extremely agile handling. The unassisted steering was ultra-quick and felt very communicative. The double wishbones suspensions provided stability yet good ride. It was very quick in corner while being so easy to handle. Excluding formula racing cars, nothing could compare with it, not even a Caterham Seven.
Part of the handling excellence was contributed by the brakes. You won't predict such a flyweight to use such high-specification brakes - front ventilated and cross-drilled discs with 4-piston Brembo calipers, rear cross-drilled discs with 2-piston calipers, also from Brembo. As described by Gordon Murray, "It is the only car I know that you can thrash round a circuit all day without so much as a wisp of smoke from the brakes, and then jump in and drive it home".
Rocket is still for sale to special order, although the price is very high (about a Lotus Esprit GT3), although it is virtually impractical in any sense (no weather protection, no boot, no equipment, the 1+1 seating plan is no use for adult passenger), it is still a worthy experience to car enthusiasts. It is never a vehicle for transportation purpose, it is purely driven for fun.
Lamborghini LM002 (1984)
If you know Ferruccio Lamborghini made his wealth in tractor business before establishing his supercar company, you won't be surprised to see the Lamborghini super off-roader. Like AM General's Hummer, Lamborghini LM002 was designed with military function very much in mind, especially in the Middle East market. The 3-ton body seated 4 people in the cabin and optionally another 4 in the open cargo area. Power came from Countach's 48-valve 5.2-litre V12, with 455 hp and 369 lbft to make it the fastest off-roader in the world.
Commercially, LM002 was quite successful. The Saudi Arabian army ordered 300 cars, the first 143 had the Countach engine and the rest were delivered with the Diablo engine (5.7 litres, 485 hp, 428 lbft). Many other private customers bought it just for fun.
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