The MT900 was designed by Rod Trenne, who previously worked on the Corvette C5. The name stood for Mosler, Trenne, and the car's 900 kilogram (1984 lb) target weight.
The MT900 used a carbon-fiber chassis with a LS1 V8 engine mounted amidships, powering the rear wheels. Power output is 350 hp (261 kW), with 350 lb·ft (475 N·m) of torque. A ZF transaxle, designed for Porsche, was mounted upside down to allow the engine to sit in front of the rear axle.
The original MT900 weighed 1175 kg (2590 lb), much more than the target weight, but could still accelerate to 60 mph (97 km/h) in 3.5 seconds according to Car and Driver. The MT900 they tested could also do a 12.0 second quarter mile at 118 mph (190 km/h), and they recorded a top speed of 150 mph (241 km/h), limited by the redline. More impressive, the MT900 pulled 1.02 g on the skidpad. The U.S. Environmental Protection Agency estimated 19 and 28 mpg (12.4 and 8.4 L/100 km) in city and highway driving, respectively.
The car had a somewhat plain exterior designed for aerodynamics, with a low 0.25 coefficient of drag. List price was US$164,000. Sales were certainly slow, and only a single prototype produced.
Introduced at the same time as the basic MT900 was the race-ready MT900R. It was designed for use in various international motorsports series for an estimated price of $119,000. The MT900R made its competition debut at the 2001 24 Hours of Daytona, and would be campaigned by a factory Mosler team for the full season of the Grand American Road Racing Championship. The entry finished the year ninth in their class championship.
For 2002, the French Perspective Racing team would become the full-season entry in Grand American and saw an improvement in performance. At Daytona the MT900R finished 13th overall and fifth in their class before winning at the next round at Homestead-Miami Speedway, helping the team to third in the championship. Rollcentre Racing and Balfe Motorsport (with aid from Rollcentre) would bring the Moslers to Europe in 2003, starting the British GT Championship year strong with three straight one-two finishes, before finishing the year with four more victories. The Rollcentre squad edged out Balfe for the championship that year. In Grand American, the Moslers were moved to the faster GTS class, but Perspective Racing improved on the previous year's Daytona effort with a ninth-place finish and the class victory. Mosler Automotive would take one more victory that season.
Martin Short's Rollcentre Racing team also took their MT900R to a second-place finish in the inaugural Bathurst 24 Hour in 2002 at the famous Mount Panorama Circuit in Bathurst, Australia. Rollcentre backed this up in the 2003 race with a fifth-place finish. The MT900R proved very quick on the circuit's Mountain and Conrod Straight's (both over 1 km in length), with Short finding he was able to match the speed of the Holden Monaro 427C's which used an Australian developed version of the larger 7.0L (427cui) V8 engine used in the Chevrolet Corvette C5-R's at Le Mans, as well as the 6.0L V12 powered Lamborghini Diablo GTR.
Rollcentre and Balfe would continue in the British GT Championship in 2004, although Balfe would also enter the Spanish GT Championship. The Moslers would struggle in British GT and score no wins, but Balfe was able to earn two victories in Spanish GT, winning the drivers' championship by a mere point. 2005 would see Balfe entering the FIA GT Championship, although the car was not homologated and could not fight for points. Rollcentre would go on to win the Britcar 24 hours at Silverstone. Escuderia Bengala and Escuderia Motor Terrasa would compete in Spanish GT, while Eclipse Motorsport and Cadena GTC took over British GT competition.
Launched in late 2006, the Mosler MT900 GT3 was an attempt by Rollcentre Racing to adapt the MT900R for compliance to the new FIA GT3 category used in various championships. However, the lack of production Moslers led to the FIA rejecting the homologation and forcing Rollcentre to turn elsewhere. The car is allowed into the International GT Open, Australian GT Championship and Belcar series along with the British GT championship which runs to GT3 rules, but has not been approved for other series which use the GT3 category. MT900R GT3's use the LS7 7.0L V8 (427cui) rather than the LS1 5.7L (350cui) version from the original MT900R.
The MT900 underwent several changes to become the MT900S. It now delivers 435 hp (324 kW) from its Corvette Z06-derived LS6 V8. The car weighs 2200 lb (998 kg) without fuel.
An early prototype MT900S, despite being up 390 lb (177 kg) and down 65 hp (48 kW) from the production version, posted a 0-60 time of 3.5 seconds and a quarter-mile time of 12 seconds flat.
A newer edition featuring 600 bhp (450 kW) prestated 0-60 mph in 3.1 seconds in Car & Drivers test in early 2006.
In June 2005, Mosler announced that they had reached EPA and California Air Resources Board (CARB) certification on the MT900S, finally allowing road car sales to begin in the United States. The price was set at $189,000 with two examples having been built as of January 2005. George Lucas took delivery of the first street-legal MT900S in December 2006.
Type: supercharged and intercooled V-8, aluminium block and heads
Bore x stroke: 3.90 x 3.62 in, 99.0 x 92.0 mm
Displacement: 346 in³, 5665 cc
Compression ratio: 10.5:1
Fuel-delivery system: port injection
Supercharger: Eaton, Roots type
Maximum boost pressure: 6.0 psi
Valve gear: pushrods, 2 valves per cylinder, hydraulic lifters
Power (SAE net): 600 bhp (450 kW) @ 6300 rpm
Torque (SAE net): 557 lb·ft (755 N·m) @ 4000 rpm
Redline: 6500 rpm
Transmission: 6-speed manual
Final-drive ratio: 3.44:1, limited slip
Gear, Ratio, mph/1,000 rpm, Speed in gears
I, 3.82, 6.1, 40 mph (6500 rpm)
II, 2.15, 10.9, 71 mph (6500 rpm)
III, 1.56, 15.0, 98 mph (6500 rpm)
IV, 1.21, 19.4, 126 mph (6500 rpm)
V, 1.00, 23.4, 152 mph (6500 rpm)
VI, 0.85, 27.6, 179 mph (6500 rpm)
0 to 60 mph (97 km/h): 3.1 s
0 to 100 mph (160 km/h): 6.5 s
0 to 150 mph (240 km/h): 13.8 s
Street start, 5–60 mph: 3.7 s
Top-gear acceleration, 30–50 mph: 4.7 s
Top-gear acceleration, 50–70 mph: 3.8 s
Standing quarter-mile (400 m):386798637 11.0 s at 135 mph (217 km/h)
Top speed (redline limited): 179 mph (288 km/h)
A MT900S Photon variant is available which adds a Hewland transmission, thinwall subframes, Dymag carbon fiber magnesium wheels, titanium springs, and carbon fiber seats and bodywork, reducing the car's weight to just under its initial target at 898 kg (1980 lb). This is technically a $50,000 option package for the MT900S. As of January, 2011, a second Photon had been built and was sold for use in the United Kingdom.
In 2010, Mosler announced they would release a facelifted version of MT900, based on the MT900M which participated in 2010 Super GT season. A rendering was made of the facelifted MT900 which was as far as the redesign progressed. In May 2011 production was stopped and the factory closed down.
In 2010 Super GT season, the MT900M made its debut at the second round of the season in Okayama by Thunder Asia Racing, a GT300 team based in Singapore, unlike the other MT900 entered in previous Super GT seasons, it uses a 3.4L V8 Judd powered Engine, an Aero kit specified for GT300 class' regulation is used.