In 1992 Marcos left the kit car business, all cars from this point onwards being factory built, and launched the Marcos Mantara which was sold through dealers in limited numbers. The main difference between the Mantara and the Mantula was the adoption of MacPherson strut front suspension in place of the Triumph suspension and associated trunnions. This change resulted in a wider front track, different bonnet, and flared front arches. The rear wheel arches and rear lights were also changed to give the car a more modern appearance. Power steering was also available for the first time. The Mantara was powered as standard by a 3.9 litre fuel injected Rover V8 or a 4.6 litre Rover V8 as an optional alternative.

The Marcos GTS was a version of the Mantara powered by the 2-litre Rover Tomcat engine. The top version was the 200 bhp (149 kW; 203 PS) turbo version. The GTS version of the Mantara had a slightly different bonnet incorporating much smoother lines, flared-in headlamps, and a deeper spoiler, which was used on the later Mantaray model. A handful of late Mantara V8's were produced with the same bonnet as the 2.0 litre GTS.

For a return to GT racing, a range of modified Mantaras was also produced in the LM (Le Mans) versions. In order to qualify as a production vehicle, a limited number of road going cars were also made. Several versions of the LM were made such as the LM400 (with a Rover 3.9-litre V8 engine), LM500 (Rover 5-litre V8) and LM600 (with 6-litre Chevrolet small-block V8). Only 30 road-going LM cars were ever built, and of these only one was a road-going LM600.