During the March 1999 Geneva Auto Show, Automobili Lamborghini SpA showed the limited edition Diablo GT, only 80 cars were to be made of this special Gran Turismo Diablo, a car capable of carrying you to a top speed of 210 mph.
But on a late 1999 Bologna Motor Show, Lamborghini had an evolution of this GT ready, the Diablo GT-R was a race-ready version of the street legal GT (although it never was legal in the United States and Japan). The Diablo GTR production will be limited to only 40 units, but this car was ready to be raced by a select few in the Lamborghini Supertrophy, organized by the Stephane Ratel Racing Organisation.
The Diablo GTR was in fact the true successor to the Diablo SVR which was used for four consecutive years with great success as a true race car in the special Lamborghini Supertrophy, this GTR has set new boundaries in this Supertrophy, with 590 hp the GTR outpowers the SVR by 50 hp.
A true race oriented chassis has been created, this time with a fully integrated roll-over cage protecting the driver in case of a crash, the massive rear wing was actually directly bolted onto this lightweight chassis. Also the brakes were again upgraded to full Brembo race specifications, the Lucas electronically controlled ABS was however still mounted.
The top speed of this GTR was set at 216 mph., the 6-Litre V-12 engine now produced 590 hp instead of the standard 575 hp from the Diablo GT, still using the five-speed gearbox all this power is transmitted to the light-weight magnesium Speedline 18-inch rear wheels.
The power output of this magnificent V-12 was obtained by using a multi-throttle intake manifold with an individual intake system, a variable intake valve timing system, dynamic air inlet duct system upstream of the intake plenum and titanium connecting rods coupled to a lightened crankshaft. Also responsible for the higher power output was a specially tuned race oriented exhaust system without catalysts and a new improved programming of the engine management system.
Additional cooling systems were mounted for the gearbox and differential oil to cope with the higher demands of racing an exotic V-12 engine, last but not least a special racing type fuel cell was installed replacing the standard tank used on the Diablo GT. The massive single piece 18-inch lightweight magnesium wheels used a race type, one-bolt central locking mechanism with an 85mm bolt, these wheels were designed to accept both standard tires and racing slicks from Pirelli.
The brakes received special racing calipers to match the increase in power, almost the entire body of this GTR was made of Carbon Fibre, only the roof remained in steel for torsional strength while both doors were kept in aluminium for safety reasons.
On the inside the Diablo GTR was also stripped of all unnecessary items, the air conditioning was gone while the passenger seat was also removed, the driver seat now was a light-weight Carbon-Fibre bucket seat with a six-point racing harness, also because this seat was wider than the original seats of the GT, the central transmission tunnel became smaller. The standard buttons were replaced by racing switches, while an obligatory fire extinguisher system from Momo was mounted on the right side of the cockpit with the option of turning it on with a button located on the central tunnel. Also the allready custom steering wheel of the Diablo GT had been replaced by an even lighter race-type unit.
To loose even more weight the side windows were replaced with Plexiglass units, incorporating a small sliding part instead of winding down. Just behind the exterior rear view mirror an air intake was mounted, guiding fresh air into the driver’s compartment which could become rather warm during a race, since the isolation between the driver and the engine was also removed to gain even more weightreduction.