Developed in tandem with the T.33 coupe, Gordon Murray Automotive has now officially released details of the OEM’s new T.33 Spider, a supercar with removeable roof panels and a naturally aspirated Cosworth GMA.2 V12 installed behind the interior cabin.
Built around an ultralight carbon-fiber monocoque construction, the T.33 Spider has been developed to deliver excellent torsional stiffness to ensure it delivers a high level of handling performance and agility without adding unnecessary weight. GMA’s latest model uses all-round double wishbone suspension and high-pressure monotube dampers made from lightweight aluminum. The decision was made by the engineering team not to offer adaptive damping, and instead the team calibrated the suspension setup to provide an optimal ride and handling balance.
Drawing inspiration from the world of motorsport, the T.33 Spider’s powertrain is semi structural, with the rear suspension setup mounted directly to the transmission casing. Furthermore, to maximize the weight reduction and to deliver vehicle dynamics benefits without causing additional noise or vibration in the cabin, GMA has implemented its inclined axis shear mounting (IASM). The IASM system uses flexible mountings to deliver the right amount of isolation required for refinement while also enabling precise handling.
Delivering power for the T.33 Spider is the Cosworth GMA.2 V12. The naturally aspirated 3.9-liter, all-aluminum engine benefits from a 65° cylinder bank angle to optimize its packaging within the vehicle monocoque while keeping the center of gravity as low as possible. A dry sump and Inconel exhaust manifolds also feature.
Air is fed into the V12 via a ram air scoop and four throttle bodies, partnered with two fuel injectors per cylinder. The use of titanium for vital engine components including the connecting rods ensures that 75% of the 451Nm maximum rated torque is available from 2,500rpm, while 90% is maintained from 4,500-10,500rpm.
The T.33 Spider can deliver a peak power output of 617ps at 10,250rpm, ahead of the 11,100rpm electronic limiter. The entire Cosworth engine weighs just 178kg, making the powertrain the world’s lightest road car V12 engine. Much like the T.33 coupe, the Spider will be offered with a six-speed manual transmission which weighs only 82kg.
Stopping power is provided via a carbon ceramic matrix (CCM) braking system that has been developed specifically for the T.33 coupe and T.33 Spider. The system features 370mm x 34mm discs and six-piston monobloc calipers on the front axle, partnered with 340mm x 34mm discs with four-piston monobloc calipers at the rear. Creating contact with the driving surface are 19in wheels at the front and 20in wheels at the rear, shod in 235/35 ZR19 and 295/30 ZR20 Michelin Pilot Sport 4 S tires.
As first introduced on the T.33 coupe, the T.33 Spider also features GMA’s Passive Boundary Layer Control (PBLC) system. The PBLC has been further refined for the Spider and consists of a ground-effect inlet at the front of the car to direct low-pressure air underneath the floor. This is then directed into a rear diffuser with a boundary layer removal duct. When used in combination with the deployable active rear spoiler, PBLC delivers a balance of low drag, high downforce and high-speed stability.
“When drawing a car, I imagine what it’s going to feel like to sit in, and how it will feel to drive,” explained Professor Gordon Murray CBE. “So from the first sketch I knew that, with its open cockpit and the incredible Cosworth GMA.2 V12 engine right behind you, the T.33 Spider would deliver a truly involving driving experience that’s quite unlike anything else.”
All 100 production examples of the T.33 Spider will be hand-built at Highams Park, GMA’s all-new bespoke headquarters in Windlesham, UK.