I have been thinking about the gearing for our clubman van and have to start making decisions, hence the questions in the gearbox thread. The motor will be 1360 with a mild cam, modified head single 1.75, in other words it is going to be built for torque. Cam will be a megadyne (mildish). Now I have to make some decisions on wheel sizes, diff ratios, etc. This van will be driven loaded between Wakefield and Sydney regularly so its ability to handle steep hills and 110 speed limits needs to be thought out. What wheel size, 10's or 12's? Once I sort that out I can then ask the question about ratios for the diff. Also if I recall the overall ratio can be affected by the primary/drop gears? its a long time since I looked at any of this stuff. If I am going to replace the sccr box and gears what primary ratio do I need. Help and suggestions greatly appreciated. BTW it won't get driven in traffic much at all.

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Chris

Everything I like is either
illegal, immoral or fattening.

If you are going to run helical drop gears (to reduce noise you have) they are generally 1:1 ratio (with S or Mini-K box). If you fit later Metro ones (finer teeth) there is an `economy gear' you can get, I think 1.08:1 or thereabouts.
Whether 10" or 12" wheels will not affect gearing much, as they are nearly same diameter. (165/70-10 & 165/60-12).
For cruising (& a bit of towing as you said before) I would run a 3.44 diff, or perhaps a later 3.1 if you find one. If you go for the 1.08 drop gears I would stay with a 3.44.

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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.

Ah, the light dawns. So the 12's were to get the bigger brakes under the wheels, not a gearing issue. I reckon they look better on 10's and I already have a set of them. I might just build some proper metal ducting for the brakes and put brakes on the trailer even if it is light enough for two people to lift. Can I get two calipers on each front rotor?

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Chris

Everything I like is either
illegal, immoral or fattening.

Chris....the Doctor is correct about not much difference in Rolling Diameter between 10s and 12s ....but if you are really going to be racking up the clicks maybe the 12s will give you more tyre choices...and maybe a little more puncture resistance on some of our magnificent roads.....just a thought.

I'm no expert but I would have thought that good 2 or 4 pot calipers, EBC pads etc should give you the required breaking performance without going to the complication of twin caliper fronts!

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"Show me the Mini!"

No room for 2 calipers- steering arm is in the way.
If you're buying calipers, 4 spot calipers are better than S ones but cost a little more $$$.

OTOH, if you were to go to 12" wheels you have more brake choices- 8.4s, Metro turbo ventilated 8.4", Honda 9.1", Camira 9.2". All have a lot more swept area than S brakes.

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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.

Tire choice for 12" is basically limited to Falkens and Yoko A539's, Go the 12's for the better braking options and we all know clubmans look better with 12's

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Starlet Conversion:
http://www.ausmini.com/forums/viewtopic.php?t=15484

I sold a Suzuki due to lack of tyre choice in 12's. Yokos don't appeal as they are generally to soft and Falkens definitly don't appeal at all. I might research tyres first then and see if any others are available. Thanks for the heads up on that.

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Chris

Everything I like is either
illegal, immoral or fattening.

I'm running the Falkens at the moment and they are worthless when it comes to performance, but what you get is an OK dry tire..totally useless wet tire and really good tire life, the damn things last forever, i can't wait wait till they die so i can replace them with the A539s..

But you basically have your two options, Hard long wearing compound of the falken, which for towing karts around i would think they'd be a good choice, and the soft sticky compund of the A539..on the other end of the scale. There may be one or two other tires available. I'd be interested to see what you come up with.

What options to 10" guys have? A008's, Falkens and Bridgestones?..oh there are those snow tires kazjim has on his turbo, but that's a different story..

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Starlet Conversion:
http://www.ausmini.com/forums/viewtopic.php?t=15484

I will start ringing tyre distributors tomorrow. The dealers only want to sell what's easy. been there, done that. I suspect though that the choice may be down to these two and that is not good. I want good tyres that will actually enhance the performance of the car without costing me every 10,000 km. My initial choice would have been Michelin or Pirelli. There must be a wider choice in the UK I can check there as well. I will let you know.

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Chris

Everything I like is either
illegal, immoral or fattening.

Dunlop LeMans 165/70-10 were good. I still have 2, but they are pretty old. I use `em for spares.
Maybe still available overseas in 10s or 12s, I dunno.

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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.

Tyres available in 10's are so far are

Goodyear
Bridgestone
Falken
Yokohama

Goodyear was the only surprise.

Rating of performance

Yokohama
Bridgestone
Goodyear
Yokohama

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Chris

Everything I like is either
illegal, immoral or fattening.

Don't laugh...we have Northwest Tyres here that flog used europeans. The are off wrecks etc and have to undergo some sort of safety check...caveat emptor anyway...

Compounds made for autobahns etc...last forever and don't hang on all that bad....

Maybe you have a similar place down your way....another option

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"Show me the Mini!"

Found this spanish site that has a few more interesting tyres I like the Yoko A038R

http://www.theminiworld.com/tyres.htm

It may give you a few more codes to throw at the distributor.

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225hp atw on 14psi. 1/4 Mile no idea. Take one 1971 Mini Clubman, one Starlet GT Halfcut, Simmer over a warm MIG Welder, and Voila Minstar! www.mpdesign.id.au

Good find. Yokohama haven't even got A008's on their website here. I had to ring them to ask. The A32R must be a real sticky semi road tyre as it is a dearer price than the 008's. Yokohama were adamant that the 008's were the only choice from their stock. Interesting for those who wanted a semi track tyre I reckon. I just spoke to Yokohama and these are a race tyre and only available through their competition network.

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Chris

Everything I like is either
illegal, immoral or fattening.

Yes, but they are street legal if you can stand the wear. I can't- so I run A008s.
A032R available thru Gordon Leven Tyres, Emu Plains. phone (02) 4735 4500

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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.