My MG's Garage 





These specifications are presented in good faith researching information from various sources.   However, no guarantee or warranty is given to the accuracy of the above information.   You are advised to verify the correctness of these specifications prior to using them.  Use of these specifications assumes agreement with the disclaimer below. They are provided as a convenience to fellow enthusiasts and the author makes no expressed warranty to their accuracy, use at your own risk.

Model Year1971-1973
ModelMk III
Vehicle Number Location 
Body Number LocationTop left-hand side if the front bulkhead
Engine Number LocationMetal plate right-hand side of cylinder block
Gearbox Number LocationTop of gearbox, left of dipstick and filler plug
Rear Axle Number LocationFront of left-hand axle tube by spring seat
Tune Up 
Engine Firing Order1, 3, 4, 2
Valve Rocker Clearance.015 in (.38 mm ) cold
Idle Speed850 rpm
Static Ignition Timing 
Dynamic Ignition Timing1971-1972 - 16 BTDC @ 1500 rpm; 1973-1974 - 11 BTDC @ 1500 rpm
Timing Mark LocationNotch on crankshaft pulley, pointers on timing chain cover
Distributor Make/TypeLucas 25D
Contact Breaker (points) Gap.014 to .016 in (.36 to .41 mm)
Rotation of Rotoranti-clockwise
Dwell Angle60 +/-3 degrees
Ignition Coil Make/TypeLucas 12 volt
Spark Plug Make/TypeChampion N-9Y
Spark Plug Gap.025 in (.64 mm)
Carburetor Make/TypeTwin SU HIF4
Carburetor Main Jet.090"
Carburetor Main Jet NeedleAAU, ABD
Carburetor Piston Springred
Vehicle & Engine 
Length12 ft 8 1/2 in (3.8 m), 12 ft 9 3/16 in (3.89 m) w/ Bumper overriders
Width4 ft 11 15/16 in (152.3 cm)
Height4 ft 1 3/8 in (125.4 cm)
Ground Clearance5 in (12.7 cm) min.
Track Front4 ft 1 in (124.4 cm)
Track Rear4 ft 1 1/4 in (125 cm)
Wheelbase7 ft 7 in (231.1 cm)
Turning Circle32 ft (9.75 m)
Toe-In1/16 to 3/32 in (1.5 to 2.3 mm)
Empty Weight2303 lb (1044 kg)
Curb Weight2653 lb (1203 kg)
Gross Weight2753 lb (1249 kg) max
Original Tire Size165-14
Original Tire Pressure Front (Cold)20
Original Tire Pressure Rear (Cold)24
Replacement Tire Size165SR-14
Engine Type4 cyl inline ohv 5 Bearing
Engine Displacement1798 cc (109.8 ci)
Firing Order1, 3, 4, 2
Compression Ratio8.0:1
Engine Bore3.16 in (80.26 mm)
Engine Stroke3.5 in (89 mm)
Number of Cylinders4
Oil Pressure Idle10 to 25 lb/in2 (.7 to 1.
Oil Pressure Normal50 to 80 lb/in2 (3.5 to 5.6 kg/cm2)
Charging SystemAlternator
Ignition Typepoints
Fuel Pump Make/TypeSU type AUF 300 electric
Fuel Tank Capacity12 gal, 14 gal with evaporative loss system
Cooling System Capacity11.4 pints w/o heater, 12 pints w/ heater
Sump CapacityEarly cars -- 9 pints, 9.6 pints w/ oil cooler; late cars -- 6 pints, 7 1/4 pints w/ oil cooler
Gearbox Capacity, non-overdrive6 pints
Gearbox Capacity, overdrive7 pints

Anyone who has additional specifications, or corrections please e-mail them to the webmaster -- thanks.

Last modified: April 26, 2005

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