Specifications from the official MG Midget Series “TD” Workshop Manual.
Engine
| Type | XPAG/TD2 |
| Number of cylinders | Four |
| Bore | 2.6 in. (66.5 mm.) |
| Stroke | 3.5 in. (90 mm.) |
| Capacity | 76.3 cu. in. (1,250 cc.) |
| Compression ratio | 7.25 : 1 |
| Maximum B.H.P. | 54.4 at 5,200 r.p.m. |
| Maximum torque | 63.5 lb./ft. at 2,600 r.p.m. |
| Firing order | 1, 3, 4, 2 |
| Piston type | Aluminium, solid skirt, split |
| Piston clearance (top) | .0045 in. to .005 in. (.114 mm. to .127 mm.) |
| Piston clearance (bottom) | .0025 in. to .003 in. (.063 mm. to .076 mm.) |
| Piston ring gap | .008 in. to .013 in. (.20 mm. to .33 mm.) |
| Piston rings: 1st & 2nd | Compression |
| Piston rings: 3rd | Scraper |
| Gudgeon pin fit in piston | Hand push at 68°F (20°C) |
| Gudgeon pin fit in con. rod | .0005 in. to .001 in. (.013 mm. to .025 mm.) interference |
| Crankpin diameter | 1.8759 in. to 1.8764 in. (47.648 mm. to 47.661 mm.) |
| Connecting rod bearing type | Steel-backed copper-lead (thinwall) |
| Number of main bearings | Three |
| Main bearing type | Steel-backed white metal (thinwall) |
| Standard journal diameter | 2.126 in. to 2.1265 in. (53.999 mm. to 54.012 mm.) |
| Main bearing running clearance | .001 in. to .0025 in. (.025 mm. to .063 mm.) |
| Crankshaft end thrust taken on | Centre main bearing |
| Number of camshaft bearings | Three |
| Camshaft bearing type | White metal (front), Zinc alloy (rear and centre) |
| Camshaft end float | .005 in. to .013 in. (.125 mm. to .325 mm.) |
| Camshaft drive type | Duplex chain, 3/8 in. pitch, 60 pitches, endless |
| Valve timing markings | White chain links and “T” marks on wheels |
Exhaust Valve
| Throat diameter | 1.024 in. (26 mm.) |
| Head diameter | 1.221 in. (31 mm.) |
| Stem diameter | .315 in. (8 mm.) |
Inlet Valve
| Throat diameter | 1.181 in. (30 mm.) |
| Head diameter | 1.299 in. (33 mm.) |
| Stem diameter | .315 in. (8 mm.) |
Valve Timing
| Valve seat angle | 30° |
| Tappet type | Hollow |
| Valve lift (inlet & exhaust) | .315 in. (8 mm.) |
| Inlet valve opens (from Engine XPAG/TD2 No. 24116) | 5° before T.D.C. |
| Inlet valve closes | 45° after B.D.C. |
| Exhaust valve opens | 45° before B.D.C. |
| Exhaust valve closes | 5° after T.D.C. |
| Valve working clearance (hot) — engines up to No. 24115 | .019 in. (.48 mm.) |
| Valve working clearance (hot) — engines from No. 24116 | .012 in. (.30 mm.) |
| Valve guides | Removable |
Fuel System
| Fuel tank reserve level | Warning light on panel |
| Fuel delivery | S.U. electric pump |
| Carburetters | S.U. semi-downdraught |
| Carburetter needles | Standard: ES, Weak: AP, Rich: EM |
Clutch
| Type (up to Engine No. 9407) | Borg & Beck 7.5 in. (18.4 cm.) diameter, dry plate |
| Type (from Engine No. 9408) | Borg & Beck 8 in. (20.3 cm.) diameter, dry plate |
Gearbox
| Synchromesh | Second, third and top |
| Top gear ratio | 1.00 |
| Third gear ratio | 1.385 |
| Second gear ratio | 2.07 |
| Bottom gear ratio | 3.5 |
| Reverse gear ratio | 3.5 |
Front Suspension & Steering
| Camber (static) | Nil (tolerance ±1°) |
| Castor angle | 7° ± 0.5° with side-members parallel to road |
| Toe-in | Nil |
| King-pin inclination | 9° to 10.5° full bump |
| Track (front) | 47.5 in. (1.203 m.) |
| Track (rear) | 50 in. (1.27 m.) |
| Turning circle | 31 ft. 3 in. (9.525 m.) |
| Wheelbase | 7 ft. 10 in. (2.388 m.) |
| Tyre size | 5.50-15 |
| Tyre pressures | 18 lb./sq. in. (1.27 kg./cm²) |
Rear Axle
| Type | Semi-floating |
| Drive type | Hypoid |
| Ratio | 8/41, 8/39, or 9/41 |
| Adjustment | By spacers and special fixtures |
Brakes
| Type | Lockheed hydraulic two leading shoe (front), 9 in. diameter |
| Lining type | Ferodo MR.19 |
| Lining size (front & rear) | 8.75 in. x 1.5 in. x .187 in. |
| Rivets per lining | Twelve |
Springs
Front
| Type | Coil |
| Free length | 9.59 in. ± 1/16 in. (24.36 cm.) |
| Mean coil diameter | 3.238 in. (8.24 cm.) |
| Number of effective coils | 7.5 |
| Diameter of wire (ground) | .498 in. (1.27 cm.) |
| Maximum deflection | 4.24 in. (10.78 cm.) |
Rear
| Type | Half-elliptic |
| Length | 42 in. (106.7 cm.) |
| Width | 1.5 in. (3.81 cm.) |
| Number of leaves | Seven |
| Thickness of leaves | 7/32 in. (5.56 mm.) |
| Camber (free) | 4.094 in. (10.4 cm.) |
| Working load | 500 lb. at 0.5 in. positive camber (226.8 kg. at 12.7 mm.) |
Hydraulic Dampers
| Type | Girling or Armstrong |
Electrical
| Distributor rotation | Counter-clockwise |
| Automatic advance | 3° on crankshaft |
| Contact breaker gap (first type) | .010 in. to .012 in. (.25 mm. to .30 mm.) |
| Contact breaker gap (second type) | .014 in. to .016 in. (.36 mm. to .41 mm.) |
| Sparking plug (engines prior to No. 22735) | Champion L.10S (14 mm.), K.L.G. E.80, Lodge HN or HNP |
| Sparking plug (engines from No. 22735) | Champion NA.8 |
| Sparking plug gap | .020 in. to .022 in. (.50 mm. to .56 mm.) |
| Ignition timing | T.D.C. (full retard) |
| Charging system | C.V.C. |
| Battery | Lucas GTW9A, 51-amp. at 10 hours, 12-volt, Positive earth return |
Capacities
| Sump | 9 pints (10.8 U.S. pints, 5.1 litres); from Engine No. 14948: 10.5 pints (12.6 U.S. pints, 5.96 litres) |
| Gearbox | 1.25 pints (1.5 U.S. pints, .71 litre) |
| Rear axle | 2.25 pints (2.7 U.S. pints, 1.3 litres) |
| Cooling system | 12 pints (14.4 U.S. pints, 6.8 litres) |
| Brake fluid | 1 pint (1.2 U.S. pints, .57 litre) |
| Fuel tank | 12.5 gallons (15 U.S. gallons, 57 litres) |
General Dimensions
| Length | 145 in. (3.683 m.) |
| Width | 58.5 in. (1.489 m.) |
| Height | 53 in. (1.346 m.) |
| Ground clearance | 6 in. (15.24 cm.) |
| Weight (unladen) | 18.5 cwt. (2,072 lb., 941 kg.) |
| Weight (laden with two passengers) | 22 cwt. (2,464 lb., 1,120 kg.) |
Torque Spanner Data
| Cylinder head stud nuts | 500 lb. in. (5.75 m./kg.) |
| Connecting rod big-end bolts (to next split pin hole) | 320 lb. in. (3.7 m./kg.) |
| Main bearing cap nuts (to next split pin hole) | 750 lb. in. (8.6 m./kg.) |
| Steering wheel attachment nut | 500 lb. in. (5.75 m./kg.) |
| Gudgeon pin clamp screw | 400 lb. in. (4.6 m./kg.) |
