specifications for the 970cc cooper s engine | ||||||||||
and gearbox ratios | ||||||||||
engine number prefix 9f-sa-x | ||||||||||
| Engine Type 970cc Cooper S | cup type welch plugs x 4 (S) cam follower covers | |||||||||
| Bore | 2.780" | |||||||||
| Stroke | 2.438" | |||||||||
| capacity of combustion chamber | 21.4cc | |||||||||
| b.m.e.p. | 146 lb/sq" 2 3500-5000 rpm | |||||||||
| Bhp | 65 bhp @6500 rpm | |||||||||
| Torque | 55 ft/lb @3500 | |||||||||
| Fuel System | leaded | |||||||||
| Compression Ratio | 9.5:1 | |||||||||
| Firing Order | 1 3 4 2 | |||||||||
| Valve Clearance (Inlet) | .015" thou | |||||||||
| Valve Clearance (Exhaust) | .015" thou | |||||||||
| Cylinder Head Tension | 42 ft/lb * extra stud over water pump 25 ft/lb | |||||||||
| Conrod Bolt Tension | 46 ft/lb = cooper S | |||||||||
| Main Bearing Tension | 67 ft/lb= bolts 57ft/lb = nuts | |||||||||
| Crankshaft Pulley Tension | 70 ft/lb | |||||||||
| Flywheel Tension | 150 ft/lb | |||||||||
| Points Gap | .015" | |||||||||
| Dwell Angle in degrees | 60 + or - 5 | |||||||||
| Spark Plug Type / Gap | bp6es ngk w7dc bosch .025" | |||||||||
| Ignition Timing ( max total mech #30)distributor is mechanical advance only | 0-10 degrees BTDC (depends on fuel/comp ratio and distributor curve)original factory 3 deg btdc | |||||||||
| CO % (at idle) | 3% | |||||||||
| Oil Capacity | 5 litres incl filter | |||||||||
| Oil Filter (Industry Number) | early R2180p mid R2200p screw on z418 | |||||||||
| Oil Type / Grade | 20w/50 sg | |||||||||
| Recommended Service Interval | 3000 miles/ 5000 km | |||||||||
| Crankshaft main journal dia | 2.0005"-2.0010 (50.81-50.82mm) | |||||||||
| Main bearings running clearance | .001"-.0027" | |||||||||
| Connecting rods little end size | .8110"-.8115" | |||||||||
| Gudgeon pin press fit | .008"-.0015" interference | |||||||||
| Piston rings | width comps.047" x 3 oil .156" end gaps on comp .008"-.015" | |||||||||
| Valves mk1 | inlet head dia 1.401" exhaust 1.214" | |||||||||
| Cam timing using .021" tappet clearance | inlet opens 5# btdc inlet closes 45#abdc | exhaust opens 51# bbdc exh closes 21#atdc | ||||||||
| Valve springs free length | inner 1.705" outer 1.740" | |||||||||
| Oil pressure normal running | 75 lb/in (5.27 kg/cm2 | |||||||||
| carburettor needle twin 1-1/4" su | std an rich h6 weak eb | |||||||||
| Gearbox ratios standard ratio | close ratio | |||||||||
| helical gears top 1.0:1 | top 1.0:1 | |||||||||
| third 1.357:1 | third 1.242:1 | |||||||||
| second 1.916:1 | second 1.78:1 | |||||||||
| first 3.200:1 | first 2.57:1 | |||||||||
| reverse 3.200:1 | reverse 2.57:1 | |||||||||
| close ratio | ||||||||||
| straight cut 3 sp standard ratio | ||||||||||
| top 1.0:1 | top 1.0:1 | |||||||||
| third 1.307:1 | third 1.255:1 | |||||||||
| second 1.875:1 | second 1.722:1 | |||||||||
| first 3.077:1 | first 2.573:1 | |||||||||
| reverse 3.077:1 | reverse 2.573:1 | |||||||||
| with optional 3.44 ratio | ||||||||||
| Overall gear ratios with 3.765 standard final drive ratio | ||||||||||
| top 3.765 | top 3.44 | |||||||||
| third 5.109 | third 4.674 | |||||||||
| second 7.213 | second 6.599:1 | |||||||||
| first/reverse 12.047:1 | first/reverse 11.022:1 | |||||||||
| Optional diff ratios | 3.938:1 4.133:1 4.267:1 | |||||||||
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