|The limited edition Diablo GT not exclusive or extreme enough for you? The most famous Italian supercar manufacturer not to have a significant racing heritage decided that the GT needed a race-only analogue, and so the even more limited production GTR was created. Constructed to race in Lamborghini’s Diablo Supertrophy one-make series, the GTR starts with a standard 6-liter GT car, and the modification list then becomes rather extensive. The highlights mainly center around chassis, suspension, and ancillary system improvements (like better cooling and braking systems), but the engine does get a revised exhaust system that boosts output to 590 horsepower. While doing without the AWD system found on the VT and other models, the GTR stays glued to the pavement thanks to a huge rear wing to provide downforce at high speeds. To save weight, the body is primarily carbon fiber and the wheels are made of a lightweight magnesium alloy. Despite the intimidating nature of the GTR, it’s actually a sweetheart on the track, easy to control at the limit and very, very fast. Don’t expect to see one at your local track day, however, as only 40 were built, making this a standout among the long list of amazing but rare cars found in Forza 4.|
— Official description 
The 1999 Lamborghini Diablo GTR is a supercar by Lamborghini featured in all Xbox 360 Motorsport titles.
Upgraded with a roll cage, more power and aerodynamic improvements for more downforce, the Diablo GTR was designed as a track variant of the Lamborghini Diablo. It was entered in Lamborghini's one-make Supertrophy series across Europe.
|Speed 7.8||Handling 6.4||Acceleration 8.7||Braking 6.3||S 778
|Rivals reward from October 2018||Price: 1,050,000 CR|
|Collection Tier: 5 - Legendary (+50)|
|Top Speed: 210.8 mph (339.2 km/h)||Division: Elite Factory Racers|
|Acceleration 0-60 mph (0-97 km/h): 3.500 secs.||0-100 mph (0-161 km/h): 8.400 secs.|
|Braking 60-0 mph (97-0 km/h): 126.1 ft (38.4 m)||100-0 mph (161-0 km/h): 295.7 ft (90.1 m)|
|Lateral G's 60 mph (97 km/h): 1.35 g||120 mph (193 km/h): 1.46 g|
|1/4 Mile: 11.600 secs.|
|Conversion - Engine|
|V12 - Murciélago LP640|
|Conversion - Drivetrain|
|Conversion - Aspiration|
- Its engine can be swapped onto the Lamborghini Diablo SV in Forza Motorsport 3.
- ↑ "Forza Motorsport 4 - Cars". forzamotorsport.net. Retrieved 10-27-2018.
- ↑ topgear.com - "This racing Lamborghini Diablo GTR is a bargain*"
|1980s||Countach LP5000 QV · Jalpa · LM 002|
|1990s||Diablo GTR · Diablo SV|
|2000s||Gallardo · Gallardo Superleggera · Miura Concept · Murciélago · Murciélago LP640 · Reventón · Reventón Roadster|
|2010s||#08 Gallardo LP 560-4 · #14 - #18 Gallardo Super Trofeo · #63 Huracán Super Trofeo · Aventador J · Aventador LP700-4 · Aventador LP 750-4 SV · Centenario LP 770-4 · Huracán LP 610-4 · Gallardo LP570-4 Spyder Performante · Gallardo LP 570-4 Superleggera · Murciélago LP 670-4 SV · Sesto Elemento · Urus · Urus Concept · Veneno|
|Pre-Tuned||Aventador LP700-4 Forza Edition · Huracán LP 610-4 Horizon Edition · Reventón Forza Edition|