Lotus Elise GT1

The Lotus Elise GT1 (also known as the Lotus GT1 and known internally as Type-115) is a race car developed for grand tourer-style sports car racing starting in 1997.

Lotus Elise GT1
The lone Elise GT1 road car on display
Overview
Manufacturer	Lotus Cars
Also called	Type 115 Bitter GT1
Production	1 road car 7 race cars
Model years	1997
Assembly	Hethel, Norfolk, England
Designer	Julian Thomson
Body and chassis
Class	GT1
Body style	2-door coupe
Layout	Rear mid-engine, rear-wheel-drive
Related	Lotus Esprit GT1 Lotus Esprit S4 Lotus Elise S1 Lotus Exige S1
Powertrain
Engine	5.7 L Chevrolet V8 3.5 L Lotus Type 918 twin-turbocharged V8 (road car) 8.0 L Chrysler 356-T6 Viper V10 (Bitter GT1)
Transmission	5-speed Renault manual (road car), 6-speed sequential
Dimensions
Wheelbase	2,675 mm (105 in)
Length	4,510 mm (178 in)
Width	2,070 mm (81 in)
Height	1,100 mm (43 in)
Kerb weight	1,050 kg (2,315 lb) (road car) 950 kg (2,094 lb)
Chronology
Predecessor	Lotus Esprit GT1

Development

Lotus Cars had previously been using the Lotus Esprit GT1 –a racing version of their Lotus Esprit road car– in the BPR Global GT Series since its foundation in 1994, competing in the premiere GT1 class against the likes of the McLaren F1 GTR, Venturi 600LM, Ferrari F40 GTE and others. However, in 1997, the series came to be known as the FIA GT Championship and manufacturer involvement was increased with the new international exposure. Porsche was the first to start a new breed of racing cars in 1996, with their purpose-built homologation special known as the 911 GT1. This was quickly followed by the announcement that Mercedes-Benz planned to do the same with their CLK GTR for 1997.

Thus Lotus decided that in order to remain competitive in the GT1 class, it would be required to follow the route set forth by Porsche and Mercedes-Benz. However, the company management was aware that they lacked the resources available that Porsche and Mercedes had to create not only the race cars but also the street legal variants. Therefore at a guaranteed loss of money for the company, Lotus decided to take an alternate route- making a single road version of their new race car.

With this in mind, Lotus set about to develop their racing car. Lotus decided to abandon the aged Esprit chassis and instead turn to its new sports car, the Elise.

Lotus knew that the Elise's inline-4 engine would not be competitive so it was initially decided that the car would use the 3.5 L V8 engine from the Esprit sports car. However, testing showed that the engine was not as reliable as hoped. After installation of it in the road car, Lotus teams were left to decide whether or not to use the Lotus V8 or opt for a Chevrolet 5.7 L V8 engine from the Chevrolet Corvette, a car which Lotus had jointly developed when they had been under the ownership of General Motors. Lotus further developed the Chevrolet engine by fitting it with a carbon intake, developing a dry sump system. Initially it was an aluminium engine block, which proved to be problematic, The last 2 races at Sebring and Laguna Seca,they decided to change to a Nascar cast-iron block with 2 valves which resulted in bigger restrictors sizes of 2 x 36.8 mm.  for the Elise GT1 Race car. Seven Elise GT1 racing chassis were built, by G.T.I. racing; and financed and owned by Toine Hezemans and new President Roman Artioli, 2 cars going to the factory team GT1 Lotus Racing (1 car run by Fabien Giroix's First Racing) as well as privateers GBF UK and Martin Veyhle Racing. The factory GT1 Lotus Racing team and Veyle racing would be the only ones to opt for the Chevrolet V8 instead of the Lotus twin-turbocharged unit.

Performance

The Elise GT1's water-cooled 3.5 L Type 918 Garrett twin-turbocharged V8 engine has a power output of 550 PS|hp at 6,500 rpm and the modified 5.7 L Chevrolet V8 engine has a power output of ca 600 PS|hp|at 7,200 rpm. Only the factory cars had the Chevrolet V8 engine and the road version had the Type 918 V8 with the former proving to be more problematic. Both of the engines helped propel the car from 0 to 60 mi in 3.8 seconds and on a top speed of approximately 320 km/h The race cars were initially fitted with a Hewland 6-speed sequential manual transmission,although multiple other transmissions were used during their life span. The last 2 races of the GT championship at Sebring and Laguna Seca the factory lotus used a 2 valve Nascar engine with steel block which gave more power and was much more reliable. The road version was fitted with a Renault 5-speed manual transmission. Even with such performance figures, the car wasn't able to match the performance of its competitors at Le Mans and would see a dreadful fate.

Racing history

Debuting at Hockenheim, on 13 April (first round of the 1997 FIA GT Championship season), the three factory Elise GT1s and the privateer GBF car took to the grid. Their debut was short lived, as all four cars failed to finish, all due to alternator problems in the engine. For race two (Silverstone, 11 May), privateer GBF UK received their second car (an untested chassis bearing number 06 driven by Andrea Boldrini and Mauro Martini). Again the three factory cars suffered, failing to finish because of gearbox difficulty. GBF's Elise GT1s fared slightly better, with one of their entries actually finishing, although classified last and 25 laps down from the winner.

One of six Elise GT1 race cars following restoration

The third race of the season in Helsinki was a shorter race, featuring a smaller field (23 cars). Only three Elise GT1s were entered, but GBF was able to succeed in taking 5th place, earning them points in the championship. The other two Elise GT1s also finished the race as well, an improvement for the company.

As the season progressed, the teams began to suffer. After Helsinki was the 24 Hours of Le Mans, in which only a lone GT1 was entered due to concern over the car's ability to last 24 hours. The car had an engine block failure after 121 laps. Returning to the FIA championship at the Nürburgring, the full complement of five cars managed a best result of only 11th, while at Spa they achieved 8th, but at Zeltweg all five cars failed to finish again. The teams did not attempt the Suzuka round and again could only earn 12th place at Donington and 11th at Mugello when the series returned to Europe. The final two races in the United States saw only the factory team bring two cars, with US prepared NASCAR 5.7 ltr Chevrolet engines with 2 valves 1 cam and a cast iron block, to overcome the previous engine failures. Also because of 2 valves and weight increase the restrictor size was now 2 x 36.8 and gave more power.They managed to finish on a 13th and 5th-place. The factory squad ended the season without any points, while GBF's points finish at Helsinki earned them 8th place in the championship.

Following the 1997 season, Lotus and its parent company, Proton, decided that the GT1 was not only lacking in pace in comparison to Porsche, Mercedes-Benz and the older McLarens, but that it was also extremely expensive. The Chevrolet V8 was not a custom built race engine like its competitors, leaving it lacking in top speed while the Lotus twin-turbocharged V8 was faring even worse. The chassis was also too similar to a production car to compete with the exotic designs of other cars. The project was therefore cancelled and the factory team folded. Owner of G.T.I. racing Toine Hezemans took the complete inventory including the 2 Factory cars to Holland and the 2 cars are still in their family. The privateer teams also either folded or bought more capable cars.

Miraculously, in 2003 British squad Team Elite announced plans to purchase the Elise GT1 chassis #05 and to use in the 12 Hours of Sebring and 24 Hours of Le Mans in 2004 as a closed cockpit Le Mans prototype. This was similar to a plan by Panoz and French squad Larbre Compétition to use a Panoz Esperante GTR-1, a car which had originally competed with the Elise GT1 in FIA GT in 1997, as a closed cockpit prototype as well. The Elise would be modified to meet modern regulations as well as to attempt to bring the seven-year-old car up to speed. At Sebring, the car proved its age, lasting a mere seven laps before its transmission failed. The project was promptly cancelled.

Road version

Because Lotus planned on continuing to compete in FIA GT Championship, they decided to build a new race car for the 1997 season, due to Esprit GT1 not being powerful enough to compete with other GT1 race cars like Porsche 911 GT1, Mercedes CLK GTR and McLaren F1. Lotus was aware of the fact that they lacked enough budget to produce multiple road versions of the GT1, so they came up with another plan. Through interpretation of the rules for FIA GT, Lotus realized they would only need to build a single production car in order to meet homologation requirements. The car would not even need to be sold to a customer, it merely had to be built.

Mechanically, Lotus Elise S1's aluminum chassis was retained for the GT1, although it was heavily modified from its standard form. A new carbon fibre/ kevlar body that resembled the Elise was built, featuring a much longer length and a bigger width in order to increase the car's aerodynamic capabilities. The dimensions of the GT1 were now these: the overall length was now 4510 mm, and the overall width was 2070 mm. Width of the front axle was 2000 mm, same with the rear axle. The front overhang was 940mm and the rear was 895 mm. Wheelbase is approximately 2675 mm. All of these measurements were made from the center of the car. The weight of the car was around 1050 kg, a little heavier than its track-focused counterparts.

The road version of the GT1 was fitted with a water-cooled 3.5 L 4-stroke Lotus Type 918 Garrett twin-turbocharged V8 engine with a power output of 550 PS (542 HP) at 6,500 RPM, attached to the Renault 5-speed manual transmission. The Lotus V8 engine was proven to be unreliable, so in the process, the racing team decided to put the GM's Chevrolet Corvette V8 engine in the factory track-focused race cars. The car was also fitted with a double wishbone suspension on both front and rear and an aluminum roll cage that was bolted down to the chassis.

As of 2017, it is difficult to say where exactly the road version GT1 is. Last time it was seen in public was almost 10 years ago, at the Le Mans Classic. According to some sources it's still owned by Lotus and stored in a warehouse in England, but some say it could have ended up in the hands of a private collector in the Netherlands.

Additional information

Type 918

• Position and location of the engine: behind the driver, central rear longitudinal
• Cycle: 4-stroke
• Turbos: Garrett
• Number and layout of cylinders: V8 (90 deg)
• Type of cooling: Water
• Cylinder block material: Aluminum
• Angle between intake valve and vertical: 21° 30' to bore centre-line
• Angle between exhaust valve and vertical: 20° 30' to bore centre-line
• Camshaft location: over-head DOHC (2/head)
• Intake: 2 valves per cylinder
• Exhaust: 2 valves per cylinder

Renault Manual Gearbox

• Location: behind engine- longitudinal
• Number of teeth:
  • 1st gear- 11/37
  • 2nd gear- 17/35
  • 3rd gear- 21/29
  • 4th gear- 27/28
  • 5th gear- 41/31
  • Reverse- 11/39
• Shift gear ratio:
  • 1st gear- 3.36
  • 2nd gear- 2.06
  • 3rd gear- 1.38
  • 4th gear- 1.04
  • 5th gear- 0.76
  • Reverse- 3.54

Type of gearbox lubrication is wet sump-oil.

Final drive

• Type: spiral bevel
• Number of teeth: 9/35
• Shift gear ratio: 3.89

Type of lubrication is wet sump-oil.

Date of homologation: April 1, 1997 End of homologation: December 31, 2004

Bitter GT1

Bitter GT1 at Frankfurt Motor Show 2019

Former factory driver Mike Hezemans of the Netherlands, feeling that the Elise GT1's main faults were in its power and aerodynamics, decided that the car should not be abandoned and convinced his father Toine Hezemans to provide financial help in his project. Toine owned 2 former Elise GT1 chassis abandoned by the factory along with their inventory of parts. Hezemans and his small team consisting of chief mechanic Hans Willemsen and two mechanics, Peter Classen and Mario van Beek, set out to eliminate the known faults in the car. They took the chassis to the Netherlands and in their small workshop, the car was extensively reworked. The front end was made longer and smoother in an attempt to increase front downforce. To replace the Elise GT1's Chevrolet V8, Hezemans turned to Chrysler, buying a pair of 356-T6 8.0L V10 engines having a power output of 626 PS (460 kW; 617 hp) and 800 N⋅m (590 lb⋅ft) of torque, which were being used in Chrysler's GT2 Vipers. The engine was fitted in the car by extending the chassis. The Hewland gearbox was retained as the team had a small budget. The new cars were promised to compete in the 1998 FIA GT Championship season. In order to make the cars compliant to the regulations of the FIA, Hezemans turned to his friend Erich Bitter who was an independent German car manufacturer. He agreed to give the cars his firm's name and the car were named Bitter GT1s.

The cars never matched even the lackluster performance of the original Elise GT1s. The only race in which they actually competed, Silverstone, saw both Bitters failing to finish, as the torque produced by the new V10 engine was too much for the gearbox. The original Hewland gearbox would be replaced with a unit from Gemini Transmission but after failing to even get past initial practice at the next race at Hockenheimring, the project was cancelled.

One Bitter GT1 has survived to this day, which is still currently in the ownership of the Hezemans family. The car has been restored to its original 1998 specification by NASCAR Whelen Euro Series team Hendriks Motorsport and was shaken down in January 2021 at TT Circuit Assen by Toine's son Loris Hezemans.

External links

• Supercars.net - Elise GT1
• Bitter Cars - Bitter GT1 (Link is broken, 21 March 2017)