hey guys
on an american site it has for sale a final gear, is this an overdrive, so 4 speed plus overdrive or so on, has any one changed their 4 gear ratio to suit higher speeds,
cheers

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any parts for a 76 clubby pm me or ring 0405 329 326

http://www.ausmini.com/forums/viewtopic.php?t=44717

Final drive gear probably. aka here as`diff ratio'.
Minis here ex-factory had either 3.765 (850, 997-998 Cooper & Deluxe), 3.647 (Mini-K, 1100 Clubby), or 3.444:1 ratios (Cooper S, Clubby GT and some later Clubbys).
UK got taller ones- 3.2, 3.1, 2.95, 2.7. Rocking horse doo-doo here though.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Just on this subject of Diff ratios. Am I right to assume you can mix and match pinions with crownwheels as long as they are both helical?

HRS

Well- you are 1/2 right.
Pinions are common if teeth count the same, but not crown wheels.
eg a 3.44 diff has an 18T pinion and 62T crown wheel.
a 3.64 has a 17t pinion and a 62T crown wheel.
A 3.76 diff has a 17T pinion and a 64T crown wheel.

The 17T pinions are the same, but the 62T crownwheels are not.
make sense?

I always cable tie the pinion to the gear when I strip them apart.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

i have a 2.9 half into my 1220, and we just put a 2.9 in my mates 1275, i goes really well, and its not dificult to take off in 1st the hardest part of fitting is milling out the bearing retainer to suit larger pnion, a drum sander works well

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speed costs....how fast do you want to go...

so wat does these ratio do to make them different from each other and wat would be best to use

the lower the number eg. 2.9, the lower your RPM at a given speed will be. Hotbricks.org.au (i think) has a chart showing wheel size/diff ratio/speed/rpm, its a very good resource.

what sort of driving you do dictates what diff is best for you, for me its mostly 110kph for 2 hrs at a time, so a 2.9 suits (a 2.7 would be nice, but id want more power)

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speed costs....how fast do you want to go...

....and mine rarely gets out of the suburbs, so a worked 1360 with an S box, a 3.64 diff and 10" wheels is real good fun.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

hehehhe, how long do tyres last doc?

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speed costs....how fast do you want to go...

Well the A008s I use give me about 3 years- the thing only gets to do about 4000 miles a year now.
Falkens FK07Es lasted forever, but they lacked grip off the line when dry and were friggin hopeless in the wet.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

why am i not supprised
(my bidgstones have lasted almost a year now oh, oops thats because i blew 2 motors up and there only 2000km old! )

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speed costs....how fast do you want to go...