Usual disclaimer- don't blame me if, blah blah... 
OK you need:
1 pair of Civic or City discs & calipers fom an 83?-87 Honda (earlier/later may be OK too). No you don't need the Honda brake hoses or the hubs, but
keep the 12mm bolts you will need them.
I drum brake Mini (U got that..)
2 mounting plates 8mm thick MS for the calipers- these bolt on the drum brake swivel hubs in place of the existing backplates. Have to make- see Honda brake thread. Buy 3 new mounting bolts 5/16" UNF x 3/4" long- grade 5, 8 or Unbrako cap screws.
2 extra copper 3/8" copper washers to seal the Mini brake hoses on the Honda calipers. The threads fit pretty well, but the end of the last thread on the hose will stop it sealing unless you fit 2 washers. (S calipers are counterbored to clear but Honda are not, that's why).
Machining:
1. Bore the centre of the disc to 65.0mm
2. Turn the shoulder on front of the drum Mini drive flange to 65.0mm. Disc will now locate properly and not `run out' (wobble).
3. Drill the Honda disc for Mini stud pattern- 4 holes 10.0mm dia on 4" (101.6mm) PCD. Also drill two 7mm holes for the csk screws. Use an old drive flange for a drill jig.
4. Make 2 alloy spacers 130mm OD x 74mm ID x 25mm thick. Drill stud and screw holes as above. OR you can butcher some spacer drums to get the spacer bit... heavier though.
5. Fit Cooper S / (or Clubbie S) rear wheel studs to the drive flanges.
6. Carefully grind the little lugs off the back of the calipers where the hoses go. Don't mark the sealing face..
This is all you need to fit 9" discs with 12" or 13" wheels. Hub offset will be the same as Cooper S brakes.
If going for 10" wheels there's a little extra to do:
1. Machine disc diameter down to 7.9"
2. grind away the inside of the outer brake pad to miss the bell section of the disc
3. Trial fit the wheel (Mini offset Contessa or similar) onto the hub & caliper assembly. A little grinding will be needed to the caliper pin bracket and perhaps the claw of the caliper. There's no brake fluid in there, so a little fettling is OK.
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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 dont get it at all, what is needed for the honda conversion, and how much does it cost....can someone please give me a breakdown of parts and processes needed/used for the conversion, in simple terms plllleeease cos i have absolutely no idea. i bought my first mini unknowingly getting a 1275 from the LS mini instead of the stocky 998...with drums 
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