Production years: 1966 - 1971

In 1966 the Mark 10 was re-badged as the 420G with a modicum of trim changes like new chromed hub caps, a bold centre rib in the radiator grille and some interior trim changes. The model, although running alongside the all new XJ6 when introduced in 1968, was finally dropped from the range in 1971.

Model Summary

Model Type:

Mark 10/420G/DS420

Production Dates:

1966 - 1971

Engine Range:

3.8 Litre Saloon

4.2 Litre Saloon

0 - 60 mph:

3.8 Litre Saloon - 9.1 seconds

4.2 Litre Saloon - 9.9 seconds

Top Speed:

3.8 Litre Saloon - 119.5 mph

4.2 Litre Saloon - 121.5 mph

420G Technical Specifications

Technical Information

Engine Statistics

	3.8 Litre Saloon
Engine (cc)	3781
Bore and Stroke (mm)	87 x 106
Compression Ratio	8:1 (7:1/9:1 optional)
BHP	265
@ RPM	5500
Torque (lb ft)	260
@ RPM	4000
Fuelling	3x SU carbs

	4.2 Litre Saloon
Engine (cc)	4235
Bore and Stroke (mm)	92.07 x 106
Compression Ratio	8:1 (7:1/9:1 optional)
BHP	265
@ RPM	5400
Torque (lb ft)	283
@ RPM	4000
Fuelling	3x SU carbs

Engine Performance

	3.8 Litre Saloon
Top Speed	119.5 mph
0 - 60 mph	9.1 seconds
Fuel Consumption	14.1 mpg

	4.2 Litre Saloon
Top Speed	121.5 mph
0 - 60 mph	9.9 seconds
Fuel Consumption	14.5 mpg

Model Specifications

	3.8 Litre Saloon
Transmission	4-speed (3 synchro) BW 3-speed auto
Wheel Size (in)	14, steel
Suspension (Front)	Ind semi-trailing wishbones, coil springs, anti-roll bar
Suspension (Rear)	Ind lower wishbone/upper driveshaft link, radius arms, coil springs
Brakes	4-wheel disc, rear inboard

	4.2 Litre Saloon
Transmission	4-speed (3 synchro) BW 3-speed auto
Wheel Size (in)	14, steel
Suspension (Front)	Ind semi-trailing wishbones, coil springs, anti-roll bar
Suspension (Rear)	Ind lower wishbone/upper driveshaft link, radius arms, coil springs
Brakes	4-wheel disc, rear inboard

Model Dimensions

	3.8 Litre Saloon
Length (in)	202
Width (in)	76
Height (in)	54.75
Wheelbase (in)	120
Front Track (in)	58
Rear Track (in)	58
Weight (Cwt)	37

	4.2 Litre Saloon
Length (in)	202
Width (in)	76
Height (in)	54.75
Wheelbase (in)	120
Front Track (in)	58
Rear Track (in)	58
Weight (Cwt)	37

Optional Extras

Choice of three radio installations with or without rear parcel shelf-mounted speaker
Electric radio aerial
Wind-up radio aerial
Electrically operated windows (front and rear)
Laminated windscreen
Witter tow bar
Heated rear screen (earlier cars)
Front seat belts
Choice of radial, town and country, or whitewall tyres
Borg Warner automatic transmission
Overdrive (for non-overdrive-equipped manual transmission cars)
Fire extinguisher
Sundym tinted windscreen and side windows
Wing mirrors
Integrated ignition/starter switch to steering column
Limousine appointments (only available on ordering a new car)