Gearbox & Speedo Ratio Calculator
Guessworks Feature Product - 5/8 16TPI Whitworth Form Crankshaft Tap
The thread down the centre of the crankshaft can often be bruised which makes fitting either the flywheel retaining bolt or the pulley bolt a little difficult. This tap is the correctly profiled Whitworth form 5/8 16TPI thread and is ideal for chasing out a damaged thread.
These taps are being made at an affordable price of £50 each.
more....... £ 50.00
Tyre Size
145 x 10
165/70 x 10
145/70 x 12
165/60 x 12
175/50 x 13
195/45 x 13
Drop Gear Ratio
1:1 (Standard)
1.0416:1 (24/25)
1.0435:1 (23/24)
1.0450:1 (22/23)
1.0869:1 (23/25)
1.0900:1 (22/24)
0.9580:1 (24/23)
0.9655:1 (29/28 A+ Std Primary/eco Input)
0.9333:1 (30/28 A+ economy gears)
Gearbox type
MKI Mini Pre '64 (Magic Wand)
MKI/II Mini Post '64 (Magic Wand)
MkI/II Cooper & MkI/II/III Cooper 'S'
MkI/II/III Cooper 'S' (Close Ratio / Straight Cut )
MkIII Cooper 'S' & 1275 GT (Close Ratio)
MKIII/IV Mini & Metro (pre A+ <'84)
MKV/VI/VII Mini, ERA Turbo & Metro (A+ >'84)
Metro 1.3 HLE (Double grove A+)
Minispares (Clubman ratios CR/SC) C-STN39
Minispares (Abingdon ST ratios CR/SC) C-STN77
Minispares (Metro Challenge CR/SC) nla?
Minisport (Abingdon ST ratios CR/SC) GRBMS4014
TRAN-X (Abingdon ST ratios CR/SC)
TRAN-X (Clubman ratios CR/SC)
Quaife 4 speed Dog Kit (2.3:1 1st)
Quaife 4 speed Dog Kit (2.1:1 1st)
Minispares 5 speed Helical Gearset
Minispares 5 speed SCCR Gearset
Final Drive Ratio
2.760:1 21/58
2.950:1 20/59 ( Metro 1.3 HLE '85 on )
3.105:1 19/59 ( Metro 1.0 HLE & Some 1.3 HLE's )
3.211:1 19/61 ( MG Metro Turbo )
3.444:1 18/62 ( Most Mini's & post '84 Metro's )
3.647:1 17/62 ( Metro City, L & Van )
3.765:1 17/64 ( MKI Mini, 850's and Vans)
3.939:1 16/63 ( Option on Cooper "S" MKI/II/III )
4.133:1 15/62 ( Option on Cooper "S" MKI/II/III )
4.267:1 15/64 ( Option on Cooper "S" MKI/II/III )
4.350:1 15/65 ( Option on Cooper "S" MKI/II/III )
TPM of Speedo
1408 - 90mph Smiths central (unknown source)
1376 - 90mph Smiths central (850)
1312 - 90mph Smiths Early tri'clock
1300 - Late Cooper 110mph Nippon Seiki
1280 - 90mph Smiths central Pre 84'
1248 - 100mph Smiths (Austin 1300GT)
1248 - 120mph Smiths (1275 GT/25/1100 Special)
1242 - 90mph Nippon Seike
1216 - 90mph Smiths post '84
1120 - unknown speedo
1000 - unknown speedo
Worm & Pinion ratio
7/15
7/16
7/17
6/15
7/18
6/16
6/17
6/18
5/15
5/16
5/17
5/18
Calculated Speed by RPM in each Gear
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8000
RPM
Actual Speed vs (Speedo Reading)
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