Midget Gearbox

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RogerRust
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Midget Gearbox

Post by RogerRust »

Sophie has a smooth case midget gearbox bolted onto her 948 engine.
Does anyone know the ratios and if it will have a reversing light switch.
Alternatively where do I find the midget owners message board?
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bmcecosse
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Post by bmcecosse »

I doubt the ratios will be any different - BMC just used what was available when making Spridget. Almost certainly no reverse light! They were not 'invented' in those days for production cars.
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ian-s
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Post by ian-s »

Although I can't find any definitive information , I believe the smooth case Midget box is slightly different to the Minor - it has a slightly higher first gear. I fitted one some time ago but did not continue with it as the synchro was so weak.
RogerRust
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Post by RogerRust »

I've found the info now;

its a later 948 sprite/midget gearbox with baulk ring syncro. the ratios are 1st 3.2, 2nd 1.92, 3rd 1.14 and 4th 1:1
so its slightly higher in 1-3 and closer ratio.

see http://www.austin-healeys.com/spritespecs.htm#Gearbox
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bmcecosse
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Post by bmcecosse »

I don't think 'baulk ring' was ever fitted in the smooth case box.
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ian-s
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Post by ian-s »

I see you didn't fall into the same error as those thech pages you consulted . The gearbox ratios are as you said . The overall drive train ratios (gearbox + axle) are what the tech pages show. The early sprite box I fitted was definitely early Sprite and definitely non baulk ring, but Idon't know what year it was from. So long as the box is working alright it doesn't much matter.
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d_harris
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Post by d_harris »

I believe the later 948 box has a reversing light take-off, I will have to ask Matt

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