I thought the 3 drop gears were factory SC ?
Seeing as 3 drop gears sap power and 2 drop gears will make the car go backwards. what about a chain/belt drive instead of the gears?
Will this free up some power and still have the wear life needed for a hotted up daily driver?

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Respect mine and I'll respect yours.

I have straight cuts in my car and yes they are bloody loud but on the same note it is a nice sound. I wouldnt put them in a car that I drove fairly regularly because it would just become to much. I got them from minispares in the UK two years ago and have done lots of street driving and about 10 track days with no worries.

I also have a 4.1 LSD and the combination doesnt really make for easy street driving but it is quick off the lights, however some times less extreme makes it alot more practical and comfortable to drive. Probably wouldnt do it the same again for the street.

Imagine dealing with the distributor! It would have driven me to distraction setting the points....

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

I should have included 'own' in their too.



Factory gear failed from fatigue



This was fitted to an every day driver, stock engine and driven 'sensibly'. I have seen more of these than I care to count on.

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GT Mowog wrote
"Some after market stuff these days is little more than rubbish, that is true, however, there are at least a couple of manufacturer's products that are way better than anything the factory made.

Do your homework and looking at price WILL give you a bum steer (the best - off the shelf - I found were not the dearest, by a long way!)"

I must be missing something here. GT Mowog tell us about your findings. Why keep it to yourself? How did you find out which are the best? Have you tried them all? Perhaps have material specs of the all?
{MOd Edit]

The MED engineerig ones are great, good quality and top blokes at the factory in england. dad was over there the other week

Hang on!

Carter you started this post with the above and now you are telling us which is best?

Carter asked what they do. i.e. how they work or the principle behind them and acknowledged they were already going into one of his cars. Evidently there has been some discussion re: quality of the MED ones, but as stated at the beginning, the technical conversation was too vague and so he came here for clarification.

S/C """DROP GEARS""" are simply straight cut teeth (as opposed to the usual road going & factory fitted "Helical" cut gears) , used for the transfer of power from the flywheel/crank down to the gearbox,,, the first being called the primary gear, then down through the Idler gear (the middle drop gear) & then finally to the "First motion driving gear (the bottom one)

these are the 3 gears inside the primary case on the back end of a mini engine

now,,, gearbox gears are all the gears """inside""" the gearbox (after the first motion shaft driving gear -> the bottom DROP gear) & all all "INSIDE" the gearbox case & there are also Straight Cut gears avaliable to buy , in all manor of differing ratios, as opposed to the usual "helical cut (angled) gears as per factory fitment

Normally the S/C designed gears are mostly & usually & most commonly used for racing purposes,,, they were never really meant to be used on the road, as they are very noisy

the main reasons why S/C gears were introduced for racing purposes were that they offer less power loss throughout the gear train as they do not send loads sideways thrusting the ends of the gears like helical cut gears do, so therefore more power is delivered to the road than to the side thrusts of the gears & cases,,,, they are also avaliable in various different ratios to suit different corners & hills on the many different race tracks & are usually more of a Closer ratio gear kit than the "usually" broad ratio gear kits fitted in std road going minis

so,,, to answer the original question,,, S/C Drop gears are simply 3x gears with straight cut teeth , generally used for racing purposes & fitted to the back end of the engine & gearbox to facilitate drive (or power) from the flywheel/crank "DOWN" to the gearbox,,, hence the term "Drop" gears

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

So which drop gears are the best and why?

How careful dO you have to drive with SCs over helical. Is rev matching highly recommended or is that just a way to prolong life a tiny bit longer?
I understand a daily would suffer but a weekend/track car with limited use would surely see a long life from SCs??

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Tim

I suspect you're meaning a Dog Box rather than S/C's here?

A Dog Box does not use synchromesh to syncronise the various gear speeds while changing gears, they are either engauged or dis-engauged. Not a huge problem when the ratios are close, as they would be on a set for the track. On a road car, it would be horrible.

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So I understand what going up or down in gear size (No. of teeth) does to a crownwheel & pinion, but I see that drop gears come with different numbers of teeth as well.
What does changing gear size on any of these gears achieve?

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Clubman GT....in lots of pieces

Probably the simplest way to put is is that it has a similar effect to changing diff ratios. They also - ever so slightly - further reduce losses in the gearbox.

In straight cuts there are a few different (lowering) ratios available. In pre A+ helicals as far as I am aware, you're stuck with the stock 1:1 ratios however in A+ there are one or two different (raising) ratios.

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My own home work says these are available for pre A plus straight cut. Helical not too sure.
■1:1
■1:043
■1:087