The Ultima GTR is a supercar manufactured by Ultima Sports Ltd of Hinckley, Leicestershire, England, available both in kit form and as a "turnkey" (i.e. assembled by the factory) vehicle. The design is mid engined, rear wheel drive layout, with a tubular steel space frame chassis and GRP bodywork. A convertible version called the Ultima Can-Am is also produced. Kit builders are free to source and fit a variety of engines and transmissions but the Chevrolet small block V8 supplied by American Speed mated to either a Porsche or GETRAG transaxle is the factory recommended standard, and this configuration is fitted to all turnkey cars.
Recently Ultima have focused their marketing efforts on record-breaking activities using a model equipped with a 640 bhp (brake horsepower) American Speed engine, which is called the Ultima GTR640, and subsequently, a 720 bhp (537 kW) engine which is called the GTR720. As a result, they have established the following official, independently verified records for a production car equipped with road tires and exhaust:
* Fastest 0-60 mph time: 2.6 seconds
* Fastest 0-100 mph time: 5.3 seconds
* Fastest 100-0 mph time: 3.6 seconds
* Fastest 0-100-0 mph time: 9.4 seconds
* Best performance on a skidpad: 1.176g lateral grip in a 200 ft (60 m) circle.
* Fastest road car over the 1/4 mile: 9.9 seconds
The Power-to-weight ratio for the GTR720 is more than 650 bhp (480 kW) per tonne, which is a better ratio than the Bugatti Veyron, Enzo Ferrari, Ascari A10, Koenigsegg CCX or CCGT (but less than the Koenigsegg CCXR) , and Saleen S7. However, the Ultima chassis is rated for engines up to 1,000 bhp (700 kW) and some of Ultima's customers have fitted engines producing 1,000 bhp (700 kW) or more, for a power-to-weight ratio of approximately 950 hp (708 kW)/tonne, which is approximately twice the power to weight ratio of the aforementioned supercars and nearly the same as the Caparo T1's (1170 hp/tonne, but this is a "dry" tonnage and the hp/tonne would be reduced once oil, coolant, gasoline, etc. are added, compared to the Ultima figures above which are "wet" weights).
The car has been timed lapping the Top Gear test track in 1 minute 12.8 seconds, beating the top time listed on the Top Gear television programme, as set by a Ascari A10, by over 4 seconds.