Project Mossy
A 1963 Mini 850 with a rallying spirit and a heart full of ideas.
Mossy joined the Motor Supplies fleet with a bit of a mystery under the bonnet and a whole lot of charm. Originally a humble 850, she’s since become something of a rolling experiment — part weekend fun car, part workshop testbed, and part homage to Pat Moss, from whom she takes her name.
At a glance, Mossy still looks like your average early Mini — skinny tyres, no flares, and a bit of patina that tells you she’s been used and loved. But take a closer look, and things start to get interesting.
Under the Bonnet
The engine is a cleverly built pre-A+ 998 block, bored out to +60 thou and running 998 pistons. The block’s been shaved around 4mm, but to ensure proper sealing around the water pump face, it wasn’t brought all the way down to piston height. As a result, the pistons now sit just shy of the top deck — about four thou.
The 850 crank is still in place, now with custom thrust bearings and standard 998 internals. The conrods are A+ type with press-fit gudgeon pins.
Up top sits a reshaped 295 head, ported and shaved, running standard Cooper valves. Rockers are 1.3:1 roller type, and the camshaft is a Cooper S item. Timing is via a double-row chain.
The spark is handled by a hall-effect conversion inside the trusty Lucas 25D4 distributor. Fuel and air come from a single SU H4 on a tube-steel Janspeed inlet (from a Mini Seven car), while exhaust duties are handled by a Maniflow 3-into-1 and a straight-through 1½” system all the way back. It’s just enough to let the engine breathe and growl without being too rowdy for regular use.
She also runs a lightened flywheel and a Cooper S Blue Dot clutch — more than enough for the spirited kind of driving Mossy encourages. It’s not a big-torque build, but it’s been put together thoughtfully, and once the revs are up, it goes well.
Brakes & Handling
Mossy runs a classic Cooper brake setup: 7" discs up front and non-stepped alloy drums at the rear. That combination allows reverse-offset wheels to tuck neatly under the standard arches.
Suspension is standard rubber cones with HiLo adjustment. The plan is to bring the ride height down a touch and add a set of adjustable shocks better suited to the car’s slightly more spirited nature. For now, though, it’s perfectly drivable — and lots of fun through the twisty Adelaide Hills roads.
Inside the Cabin
The interior is largely untouched, retaining its early Mini simplicity and red trim. Red carpets are in place, and there's a plan to extend that colour scheme further — especially the rather wayward door linings, which will be retrimmed to match.
The driver’s seat features a clever period-style slip-on cover that adds side support and turns it into a makeshift bucket seat. It’s very much in keeping with the car’s philosophy.
A Work in Progress
Mossy’s not finished — and we don’t really want her to be. She's an ongoing project, always with something to tweak, test, or improve.
Recent jobs have included a full LED lighting conversion (for better visibility and reduced current draw), and a Dynalite alternator install is underway to replace the old generator while keeping the classic look.
Why It Matters
Mossy isn't a show car or a trailer queen. She’s built to be driven, fettled with, and enjoyed — and in doing so, she helps us better understand the sort of things classic owners really need. Whether it’s clever upgrades that don’t scream “modern,” or just the joy of keeping something alive and kicking on today’s roads, Mossy reminds us why we do this.
If you’ve got your own Mini and want to chat about parts, upgrades, or just share your story — get in touch.
Mossy would approve.