A 1995 Porsche 911 GT2 was one of the stars of RM Sotheby's London auction on September 7, achieving £1.8m ($2.4m).

That's an increase of 117.4% on an £850,000 ($1.1m) estimate, and trumps the previous record for the model by more than £1m.

The Porsche GT2 was introduced as a competition car

The model was introduced after all-wheel drive was banned in the majority of competition races in the 1990s, meaning the end for the company's pioneering racer - the 961.

The 933 GT2 turned out to be more than up to the job. Switching to just rear-wheel drive also made the car much lighter.

To comply with homologation rules, Porsche was required to make a certain number of GT2s available to the public.

This is one of 57 produced for road users.

The lot has belonged to the same owner since it was first sold and has a mileage of just over 12,000km - rare for this model as many were used for racing.

A 1960 Ferrari 250 GT Cabriolet realised £1.2m ($1.7m).

The car is one of just 201 built and was the height of luxury at the time.

It was originally owned by Angelo Moratti (1909-1981), industrialist and former owner of football club Internazionale.

In recent years it has been expertly restored and granted Ferrari Classiche certification - meaning its major components all display matching numbers.

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