Ginetta G55 GT4.
Britcar 2026 runs just three classes, and Box3 moves into GT. Over winter, Datum led a detailed engineering programme that touched nearly every system on the car — this is the machine the whole Box3 story runs on.
Photo: Mark Houldridge
| Chassis | Ginetta G55 | Supercup car evolved to GT4 specification |
| Championship | Britcar Endurance · GT class | Blue sunstrip; GT4 machinery and G55 Supercup, BoP balanced |
| Power to weight | Max 350 bhp / tonne | GT class limit on declared weight and flywheel output |
| Engine management | Box3 / Datum ECU | Own unit; adjustable throttle response, smoother shift and part-throttle mapping |
| Driver aids | ABS + traction control | Each multi-position adjustable |
| Exhaust | Side exit | Alters packaging and rear heat management |
| Aero | G56 front bumper | Improved airflow and front-end efficiency |
| Brakes | Uprated cooling | Manages the thermal load introduced by ABS cycling |
| Driveline | Re-engineered load path | Differential to rear hubs; gearbox rebuild and new clutch |
| Data | Race-Keeper | Video and data capture on every lap |
| Engineering | Datum Engineers | Winter 2026 evolution programme |
Specification as reported in the Britcar 2026 GT-class story. Confirm the current build with the team before publication.
Why the Cayman 981?
The Box3 Cayman 981 isn’t a toy, a rental, or a gimmick. It’s a purpose-built driver-development machine — engineered to give ambitious newcomers the perfect balance of power, feedback, and reliability.
The 981 platform is the sweet spot of modern Porsche engineering: naturally aspirated, beautifully balanced, communicative, and forgiving enough for learners while offering enough performance to excite experienced drivers.
Mid-engine balance that teaches you car control the right way. Predictable handling that builds trust without hiding your mistakes. Responsive brakes and steering so you learn real technique, not bad habits. A chassis that rewards progression, lap after lap.
At Box3, we develop drivers from the ground up. The Cayman 981 is where that journey begins.
| Brakes | Upgraded pads and fluid | Consistent stopping power, full day |
| Tyres | Semi-slick / track focused | Depending on conditions |
| Alignment | Performance setup | Sharper turn-in and stability |
| Wheels | Lightweight | Reduced unsprung mass |
| Cockpit | Racing buckets and harnesses | Safety and feel |
| Data | Race-Keeper / VBox | Data and video systems for coaching |
| Reliability | Full-day running package | Pushed hard, repeatedly, safely |
This is not a stock car. It’s prepared by people who race — for people who want to learn to race.
Ginetta G55 Supercup
The step drivers most often take out of the Cayman.
Porsche Cup machinery
For drivers who want to stay with the marque they learned in.
GT Cup / Britcar testing
Race testing in national championship machinery.
Simulator training
With full data integration, between events.
For many of our drivers, the Cayman is the moment they realise racing isn’t just a dream — it’s a path.
Black, yellow, and room for your name. Livery positions are the most visible asset the team owns.
The car is photographed at every round and filmed for the UnBoxed series.