All cars featured a cocktail of Austin-Healey brakes, VW Beetle or Triumph suspension parts and BMC rear axles.

The first of the Granturas used a fibreglass body moulded to a tubular steel backbone chassis and VW Beetle-based front and rear suspension.

The Mark III also received a new front end design, with the grille mounted higher and featuring some rudimentary chrome trim.

In 1965 the latest version of the car became available as the 1800S with a cut off, square back (called a 'Manx tail' after the similarly tailless breed of cat) and round rear light clusters from the Ford Cortina.

This was an alteration made to the Grantura chassis to allow it also to be used as the basis for the new Griffith, a car that sported a V8 engine which was larger both in capacity and physical dimension.

[3] The Mk IV featured a longer wheelbase, more luxurious trim and a larger fuel tank and was the first TVR to benefit from Martin Lilley's influence.

[3] The larger-engined Mark III 1800 model of the TVR Grantura was first introduced as a road car in September 1963 and subsequently homologated for racing in April 1964.

The main reasons are that, in addition to the obvious benefits of the more powerful 1798cc BMC 'B' engine over the previous 1622cc unit, the 1964 homologation allowed use of a limited slip differential as well as wider wheel rims (5") than those permitted on the earlier 1962/63 Mk III cars (4" or 4.5").

As a competition car the TVR Grantura MkIII benefits from being eligible for a wide range of historic racing and, due to its relatively light weight and good handling characteristics, it can be very effective when competing against some of the larger engined cars, especially when, as almost all examples are, it is in the June 1965 homologated Mk III 1800 trim.

The smaller engined 1622cc Mark III cars built to the August 1962 specification are eligible to run in high profile Pre-63 events including the prestigious bi-annual Classic Le Mans race for cars that competed in period in the Le Mans 24 hours race.