Gordon Murray Automotive’s lineup of supercars grows today with the addition of the T.33 Spider. The new model features two removable roof panels for open-air motoring, allowing occupants to hear the naturally aspirated V12 engine behind the cabin.

The panels, available in various colours, are made from lightweight carbon composite and can be stowed in the front luggage compartment when not in use. The new roof required GMA to alter the bodywork from the A-pillar back, which included giving the Spider rollover protection and rear window glass that drops behind the bulkhead to enhance the open-air experience further.

Gallery: Gordon Murray Automotive T.33 Spider

Inside, the T.33 Spider is similar to its fixed-roof counterpart. At the centre of the driver’s display is a large analogue tachometer calibrated to 11,100 rpm. Two secondary screens flank the tach for climate controls and infotainment stuff, which includes wireless Apple CarPlay and Android Auto. The car has up to 295 litres (10.42 cubic feet) of storage space, including the two 90-litre (3.19 cu ft) compartments on either side of the engine.

Drivers control the vehicle with a carbon-fibre steering wheel trimmed in leather while both occupants sit in lightweight, race-inspired carbon-fibre seats with leather and Alcantara trim. The car also features aluminium alloy switchgear, pedals, and the gear shift lever.

GMA introduced its Passive Boundary Layer Control system on the T.33 and refined it for the T.33 Spider. The system allows GMA to avoid splitters, wings, ducts, and skirts to increase downforce without increasing drag. The system feeds air into an inlet at the front that moves the air to a rear diffuser. 

Gordon Murray Automotive T.33 Spider
Gordon Murray Automotive T.33 Spider
Gordon Murray Automotive T.33 Spider

Gordon Murray sketched the T.33 Spider alongside the fixed-roof version to ensure the proportions would work and that symbiosis carried over to the actual development. The Spider led the T.33 programme, with the torsional rigidity targets for the model set for the convertible. As a result, GMA is targeting the Spider to weigh about 18 kilograms (40 pounds) more than the coupe.

The T.33 Spider features lightweight, forged alloy wheels with staggered 19- and 20-inch sizes. GMA wraps them in Michelin Pilot Sport 4 S tyres. Behind those wheels are six-piston monoblock callipers and four-piston monoblock rears measuring 370 millimetres (14.56 inches) and 340 mm (13.36 in) in diameter, respectively.

Powering the T.33 Spider is the same naturally aspirated Cosworth-sourced 3.9-litre V12 engine that powers the coupe. It makes 609 bhp and 333 pound-feet of torque, sending power to the rear wheels exclusively through a six-speed manual transmission from Xtrac. 

Gordon Murray plans to produce just 100 examples of the T.33 Spider, which will be available for sale in the US just like the coupe. GMA hasn’t released pricing, but the T.33 coupe started at £1.37 million when it launched.