Jaguar updated their top-of-the-line Mark X in 1966 by releasing the 420G. From the exterior, the only distinguishing difference between the cars was a new chrome strip that ran down the side of the car. Both cars were meant for the full-size, luxury segment and aimed at the American market.
Jaguar was determined to fit the 420G with all the latest opulence. Inside was the one of the last fully wooden dashboards with an abundance of instrumentation and switchgear. To aid with the huge steel doors, helical torsion springs were installed.
The 420G sold alongside the similar Mark X for five years. Some cars omitted the signature chrome strip for two tone paint. Furthermore, several were sold with a longer wheelbase and full-width bench seat up front.
| type | Series Production Car |
| production years | 1966 – 1970 |
| built at | Coventry, England |
| engine | Inline-6 |
| block material | Cast Iron |
| valvetrain | DOHC, 2 Valves per Cyl |
| displacement | 4235 cc / 258.44 in³ |
| body / frame | Steel body over Steel Frame |
| driven wheels | RWD |
| curb weight | 1907 kg / 4200 lbs |
| wheelbase | 3048.0 mm / 120 in |
| length | 5130.8 mm / 202 in |
| width | 1938.0 mm / 76.3 in |
| height | 1384.3 mm / 54.5 in |
| BODYWORK | ||
| BODY TYPE | 4/5 seater sedan/saloon | |
| NUMBER OF DOORS | 4 | |
| DESIGNER | ||
| DIMENSIONS & WEIGHTS | ||
| WHEELBASE | 3048 mm | 120 inches |
| TRACK/TREAD (FRONT) | 1473 mm | 58 inches |
| TRACK/TREAD (REAR) | 1473 mm | 58 inches |
| LENGTH | 5131 mm | 202 inches |
| WIDTH | 1905 mm | 75 inches |
| HEIGHT | 1384 mm | 54.5 inches |
| GROUND CLEARANCE | 165 mm | 6.5 inches |
| LENGTH:WHEELBASE RATIO | 1.68 | |
| KERB WEIGHT | 1778 kg | 3920 lb |
| WEIGHT DISTRIBUTION | ||
| FUEL TANK CAPACITY | 90.9 litres | 20 [24] UK [US] gal. |
| AERODYNAMICS | ||
| DRAG COEFFICIENT | ||
| FRONTAL AREA | ||
| CDA | ||
| POWERTRAIN | ||
| ENGINE TYPE | naturally aspirated petrol | |
| ENGINE MANUFACTURER | Jaguar | |
| ENGINE CODE | ||
| CYLINDERS | Straight 6 | |
| CAPACITY | 4.2 litre 4235 cc (258.436 cu in) | |
| BORE × STROKE | 92.08 × 106 mm 3.63 × 4.17 in | |
| BORE/STROKE RATIO | 0.87 | |
| VALVE GEAR | double overhead camshaft(DOHC) 2 valves per cylinder 12 valves in total | |
| MAXIMUM POWER OUTPUT (GROSS) | 259 PS (255 bhp) (190 kW) at 5400 rpm | |
| MAXIMUM TORQUE (GROSS) | 373 Nm (275 ft·lb) (38 kgm) at 4000 rpm | |
| SPECIFIC OUTPUT (GROSS) | 44.9 kW/litre 61 ps/litre 60.2 bhp/litre 0.99 bhp/cu in | |
| SPECIFIC TORQUE (GROSS) | 88.08 Nm/litre 1.06 ft·lb/cu3 | |
| ENGINE CONSTRUCTION | ||
| SUMP | ||
| COMPRESSION RATIO | 8:1 | |
| FUEL SYSTEM | 3 SU carbs | |
| BMEP (BRAKE MEAN EFFECTIVE PRESSURE) | 1106.8 kPa (160.5 psi) | |
| MAXIMUM RPM | ||
| CRANKSHAFT BEARINGS | 7 | |
| ENGINE COOLANT | Water | |
| UNITARY CAPACITY | 705.83 cc | |
| ASPIRATION | Normal | |
| COMPRESSOR | N/A | |
| INTERCOOLER | None | |
| CATALYTIC CONVERTER | N | |
| PERFORMANCE | ||
| ACCELERATION 0-80KM/H (50MPH) | ||
| ACCELERATION 0-60MPH | ||
| ACCELERATION 0-100KM/H | ||
| ACCELERATION 0-160KM/H (100MPH) | ||
| STANDING QUARTER-MILE | ||
| STANDING KILOMETRE | ||
| MAXIMUM SPEED | 198 km/h (123 mph) | |
| POWER-TO-WEIGHT RATIO | Higher is better 145.41 PS/tonne (1000 kg) 0.15 PS/kg 106.95 kW/tonne (1000 kg) 0.11 kW/kg 143.42 bhp/tonne (1000 kg) 0.14 bhp/kg 0.06 bhp/lb | |
| WEIGHT-TO-POWER RATIO | Lower is better 9.35 kg/kW 15.62 lb/bhp | |
| FUEL CONSUMPTION | ||
| FUEL CONSUMPTION | ||
| UNIVERSAL FUEL CONSUMPTION (CALCULATED FROM THE ABOVE) | ||
| LITRES/100KM | ||
| KM/LITRE | ||
| UK MPG | ||
| US MPG | ||
| CARBON DIOXIDE EMISSIONS | ||
| CARFOLIO CALCULATED CO2 ? | ||
| VED BAND (UK) | ||
| CO2 EFFIZIENZ (DE) | ||
| CHASSIS | ||
| ENGINE POSITION | front | |
| ENGINE LAYOUT | longitudinal | |
| DRIVE WHEELS | rear wheel drive | |
| TORQUE SPLIT | N/A | |
| STEERING | ||
| TURNS LOCK-TO-LOCK | 3.000 | |
| TURNING CIRCLE | 11.30 m | |
| FRONT SUSPENSION | I.CS. | |
| REAR SUSPENSION | I.CS. | |
| WHEEL SIZE FRONT | ||
| WHEEL SIZE REAR | ||
| TYRES FRONT | ||
| TYRES REAR | ||
| BRAKES F/R | Di/Di-S | |
| FRONT BRAKE DIAMETER | ||
| REAR BRAKE DIAMETER | ||
| BRAKED AREA | 3619 cm2 | |
| GEARBOX | 4 speed manual | |
| TOP GEAR RATIO | 1 | |
| FINAL DRIVE RATIO | 3.54 | |
