Limited-run Porsche 911 GT3 is firm’s hottest track car yet

Just 77 units of the 911 GT3 R Rennsport will be produced

£822k GT3 R Rennsport can run on e-fuels as an ultra-lightweight, 620bhp successor to Porsche’s racing icon

The Porsche 911 GT3 R Rennsport has been revealed as an £822,000 limited-edition successor to the iconic Porsche 935 racer and is the firm's most potent track-only car yet.

Claimed by Porsche to "cast aside all constraints of the FIA GT3 regulations", just 77 units of the 911 GT3 R-based sports cars will be produced after its planned presentation on 28 October at Rennsport Reunion - one of the world's largest gatherings of Porsche enthusiasts. 

Two versions of the 1240kg racer are available with different specifications based on racetrack noise regulations - an unsilenced version and two silenced versions with catalytic converters.

Power comes from the same 4.2-litre six-cylinder boxer engine as the 911 GT3 R, albeit with a host of efficiency tweaks boosting its power to from 557bhp to 611bhp, its redline to 9400rpm, and its top speed from 184mph to 196mph. 

An output of 148bhp per litre is said to be "a record for a naturally aspirated engine of a GT racing car." That power is sent to the rear wheels via a six-speed sequential gearbox. 

The engine itself has been designed to run on bi-ethanol fuels and e-fuels to make it as carbon-neutral as possible in operation, however it can also run on conventional unleaded.

Thomas Luadenbach, vice president of Porsche motorsport, said "The new Porsche 911 GT3 R Rennsport offers the experience of driving a 911-based racing car in what is probably the most primal form. It gives you goose bumps whenever you look at it and combines the finest motorsport technology with a design language that is typical of Porsche."

Designed by Grant Larson and Thorsten Klein of Porsche Style, the Rennsport is said to only share the bonnet and roof with the donor car. 

The rest of the bodywork is entirely bespoke, with a stretched wheelbase and widened wheel arches, both of which sit on lowered springs and new 18in BBS alloys. 

The body itself is entirely made out of carbon fibre and is punctuated by aero-optimised fins and larger air intakes on the front wheel arches in the name of the track work for which it is intended. The exterior mirrors have also been ditched in lieu of electronic screens fed by a trio of cameras mounted on the body.

Towards the rear, it shares design elements with Porsche's racers of the past. For example, the bumper-width rear wing takes influence from the seven-time Daytona-winning Brumos Porsche 935/77, and its vertical spoiler supports are said to be reminiscent of the Porsche 962 Le Mans racer. To reduce weight, it does without grille covers and certain panels, leaving components such as the exhaust open to the elements.

More weight-saving measures have been made inside, with the removal of the front and rear passenger seats and air conditioning system. 

It also gets a plaque denoting which model number the customer has chosen, two monitors to replace the door mirrors, colour-adjustable ambient lighting, and an FIA-spec roll cage.

It will be launched with a choice of seven colours, including Star Ruby, Signal Orange, and Agate Grey Metallic [brand new for the 911 range]. 

Of those seven colours, three liveries; Rennsport Reunion Design, said to be inspired by Laguna Seca's iconic Corkscrew corner; Flacht Design, named after the town in which Porsche motorsport is based; and Speed Icon Design, bringing shades of blue said to emphasise the car's width.

Underneath, its chassis is identical to that of the GT3 R, with double wishbones at the front, a multi-link setup at the rear, and five-way adjustable shock absorbers. A bespoke basic setup is delivered to customers who can choose to make further adjustments of their own before racing, however. 

Other bespoke components include the tyres, developed by Michelin to improve warm-up time and drivability compared to other motorsport tyres.