| Country of Manufacture | Great Britain |
| Engine | |
| Manufacturer | Napier Lion |
| Cylinders | 12 - 3 banks of 4 |
| Bore | 139mm |
| Stroke | 130.2mm |
| Cubic Capacity | 22,299cc |
| Compression ratio | |
| Valves | |
| Carburettor | |
| Max. Power | 450 bhp at 2,000rpm 502 bhp at 2,200rpm |
| Engine Mounting | |
| Transmission | |
| Clutch | 16no. 11 1/4in. dry plates; hand lever to disconnect gearbox when car stationary |
| Gearbox | FBM 3 speed epicyclical |
| Ratios | .333, .666, 1. Final drive ratio 1.27 to 1 |
| Back axle | crown and bevel independently supported |
| Type of drive | Reinecker |
| Chassis | 3% nickel steel by Vickers |
| Suspension | Woodhead 1/2 elliptic springs, front and rear |
| Shock Absorbers | duplex Hartford |
| Steering Gear | Marles duplicated |
| Brakes | Alford and Alder, solid steel drums, direct or Dewandre vacuum servo. 18in dia and 1 5/8in wide |
| Wheels | Rudge-Whitworth – wire double-spoke to front, triple-spoke to rear |
| Tyres | Dunlop size 33 x 5in. to front 35 x 5in to rear. Inflated width of tyre 5.85in. |
| Dimensions | |
| Wheelbase | 12ft 1 1/2in |
| Track front | 5ft 5 1/4 in. |
| Track rear | 4ft 9 in. |
| Length | 15ft |
| Weight | 3 tons approx. dry |
| Fuel Tank Capacity | 15 gallons |
| Radiator | Serck 10gallon header tank |
| Bodywork | |
| Manufacturer | Jarvis |
| Material | metal |