Looking to convert my mini to disc brakes all round and was wondering what is the best way to do it. Any help greatly appreciated :D

Rear discs are a pretty rare thing... A bit pointless, really, given so little braking work is done by the rears. KAD has done a conversion, but the point of it is weight saving, not increased performance. MiniSport (in Adelaide) are KAD agents.

So, if you're after increased braking performance as the motivation for wanting rear discs, I'm sorry to inform you there's no benefit. I understand if your idea is to reduce maintenance (I'd do it for that reason!), but it's a fair amount of cash to splash if you're just being lazy. Only reason for it is reduced unsprung mass, which is only relevant if you've got extremely light wheels and are competing in Motorsport.

For the fronts, easiest way to to it is to pay a specialist to fit them, otherwise, you'll need to buy a full pack. It will include Disc Brake CV's (which are bigger than drum brake CV's), Disc Brake Hubs, bearings, rotors, calipers, etc.

The kit you buy will be determined by two things - wheels and budget. What size wheels do you have? If you've got 10" wheels, you can only fit Cooper S discs under them. These are 7.5" diameter - they're a very good option, well used for 45 years now. If you've got 12" or bigger wheels, you can also fit 8.4" discs under them. These discs are cheaper to buy/maintain (cheaper rotors), and were fitted to 1275LS (Clubman), Moke, and all UK Minis after 1984 (hence higher numbers produced).

Cost? You're looking at $1500+ (up to $2k) just for the S Discs, maybe as low as $1200 for 8.4" discs. These are new prices. You many find some second hand, but by the time you refurbish them, it'll end up at similar money.

There are other options, but they involve much machining, similar or higher costs, and often requiring machining rotors (so aren't as simple to maintain - buy replacement parts). A search on here will give you more info.

I'd recommend giving MiniSport a call.

What about the 7.9" discs that minisport uk sell? Ive heard they will fit under some 10" rims, but not sure which ones. Does anyone know what rims they will fit under, other than the very expensive spectrum/mb racing split rims?

Thanks Tadhg, I drive past MiniSport twice daily on my way to and from work so might haus ass and get in there one of these days lol. The car is going to be used for competition, its a twinni, so discs on rear might be a *further down the track* thing, your point of cost vs versatiity is a good one. Thanks again for the info, will be added to my ever growing doco of thigns to know.

basically nobody knows for sure what combination of wheels and brakes will definitely work, except for people who actually have them on their car. I have emailed minispares/minisport/kad with lists of their own parts asking about compatability - they reply with a vague 'maybe'

sgc is the only one I can think of who has 4 pots with 10" wheels - I believe the setup is minispares calipers, cooper S rotors and wide offset contessas

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did I tell you that I won a trophy?

Correct on all counts. I even have adjustable lower arms and caster rods in a lowered hydro setup, which MiniSpares expressly say will have 'clearance issues'. None such exist on my car.

The Contessas fit nicely over the calipers, although there's not a lot of room. Any wheel with more inner metal than those is going to struggle. I've done some pretty 'spirited' driving, and never had enough wheel flex to cause contact with the calipers so it's all good

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Simon

The adventures of an owner builder in the Tallarook Ranges

I forgot yours was the Twinni! That makes it an interesting case. What's your rear suspension? If you've got front hubs on there (front drum hubs), but locked in place (no steering), you may be able to put on the same discs at the rear as at the front. Though you'd have difficulty if you wanted to setup a handbrake. Nothing off the shelf for that. The KAD setup's almost certainly out, given it's not designed to have a driveshaft through the middle of it. Your balance will be a bit different to the average Mini, too, so it could probably use a bit more rear brake (extra weight)...

I guess ill just get the biggest brakes i can afford and put them on, if i need new shiny wheels so be it.

And with rigging a handbrake onto front discs mounted on the rear, you could get another master cylinder (motorbike or similar), hook it onto the handbrake, and plumb it into the rear lines if you run a separate braking system. Only problem would be mounting so the handbrake gets enough leverage to activate the rear brakes.

Last time I checked, hydraulic handbrakes were illegal as a parking brake... although you can add one for khanas etc.

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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.