Five different inline six engine options were offered to customers. Four of these were variants of the 4.0L Speed Six making different amounts of power and torque, depending on the trim level selected. The last was a 3.6L Speed Six which produced the same amount of power as the lowest-level 4.0L engine, although slightly less torque.
Even though there have been numerous tweaks to the TVR Tuscan's chassis and suspension, the overall size and appearance of the variants remain virtually identical apart from minor aerodynamic aids to the S model in the form of an undertray in the front and a small boot-lid spoiler on the rear.
Source: Wikipedia (original)