Components for 25 MTs were produced as of January 2005, though only about 35 road cars and 50 racing versions have officially been completed (c.20 of which are MT900S).

[1] 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 1,175 kg (2,590 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 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.

For 2002, the French Perspective Racing team would become the full-season entry in Grand American and saw an improvement in performance.

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.

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.

[citation needed] A newer edition with 600 bhp (447 kW) accelerated 0 to 60 mph (0 to 97 km/h) in 3.1 seconds in a Car and Driver test in early 2006.

[2] In June 2005, Mosler announced that they had reached EPA and California Air Resources Board (CARB) certification on the MT900S, allowing road car sales to begin in the United States.

[3] 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 (1,980 lb).

Unlike the other MT900 entered in previous Super GT seasons, it uses a 3.4-liter V8 Judd-powered engine and an aero kit specified for the GT300 class regulations.