1965model Austin Mini Cooper S 1275 Mk-I Racing Modified　

The 1965 Austin Mini Cooper S 1275 Mk-I, which emerged from a fully shuttered, climate-controlled garage, displayed its remarkably clean body to the sunlight, radiating a unique aura. For nearly 30 years, successive owners have carefully faced this vehicle, slowly refining it toward their ideal vision and specification. Truly, this is a car that has become incredibly rare over time, making such a build almost impossible to replicate!

This genuine Cooper Mk-I, adorned with the distinctive ‘S’ badge that harks back to the racing fields of the 1960s, is perfect for enjoying weekend mountain passes. With a matching-number 1275 engine and rare original parts kept safely in the garage for admiration, one could return it to its original form at any time. For enthusiasts, this is the car that turns lifelong dreams into reality: the ‘pure enjoyment’ of owning a genuine 1965 Austin Cooper S 1275 Mk-I.

This car was parallel imported, with its first Japanese registration in April of 1982 (Showa 57). The racing modifications began some 30 years ago, with previous owners initially enjoying it in its original state, as seen in the accompanying videos. If you look through automotive magazines from the 1990s, you’ll notice that classic cars, including Minis, were far more affordable than they are now, making it a much easier purchase for enthusiasts.

After enjoying it for some time in its original form—taking it out for leisurely weekend drives through winding roads—the owner found that driving on public roads was not enough to satisfy them, so they began driving on circuits. Their goal was a car that could be driven to nearby circuits, enjoyed to the fullest, and most importantly, wouldn’t break down. Eventually, the owner’s garage became a gathering spot for friends, all of whom contributed to the completion of this racing Mini.

Over the course of 20 years, they meticulously built a machine that could compete in classic car races (JCCA spec) at Tsukuba Circuit, finishing in just over 1 minute—a staggeringly fast time for a classic car! The Mini was transformed into a race-ready machine, capable of contending for first place.

The current specifications are as follows:

• Carburetor: 45mm split twin Webers, mechanical linkage
• Head: Kent GT15 big valve
• Roller Rocker: Kent
• Pistons: Aluminum JE pistons (oversized +60), bored out to 1330cc
• Crank and Rods: Rover-made
• Transmission: Remote cross-gear, straight-cut
• LSD: Quaife ATB street differential (Cusco 1.5-way differential also included)
• Alternator: Domestic alternator
• Starter: Rover-made
• Driver/Navigator seats: Microcell

The rare, matching-number original 1275 engine has been removed and stored. In its place, the engine has been swapped with a highly reliable Rover 1300, bored out to 1330cc with oversized JE pistons. This setup is designed to rev freely without worry of breaking down. The straight-cut gearbox creates a distinctive sound, further enhancing the Mini’s extraordinary character.

The carburetors are, of course, top-tier, with twin 45mm Webers perfectly tuned. The linkage from the split Weber carbs to the accelerator pedal is a masterful piece of engineering, responding instantly to even the slightest movement of the right foot—offering an exceptional throttle response that is simply superb!

To accommodate the high compression, a powerful starter has been installed. The dynamo has been upgraded to a modern domestic alternator for voltage stability, and naturally, an electronic ignition system is in place. The cooling system has also been modernized. For safety and weight reduction, the sliding side windows and latch-operated side windows have been replaced with polycarbonate (the original windows are included).

The suspension features a Quaife LSD with street differential, reinforced stabilizers, and 4-pot disc brakes for a complete performance setup. The lowered stance and 10-inch blacked-out Panasport wheels, wrapped in 165/70R10 Yokohama Advan-032R tires, give the Mini an aggressive, race-ready appearance.

The center-exit exhaust produces an incredible midrange-boosted sound. Paired with the Smiths tachometer, which reads up to 10,000 RPM, this sharp sound is pure auditory bliss for enthusiasts, with its high-pitched mechanical hum—a sound so captivating, you’ll want to listen to it all day!

All these brilliant elements exude from the nostalgic, classic look of the original Mk-I body, creating a fascinating and exhilarating experience. As soon as the engine starts, this powerful presence captivates everyone around, and it stands strong with an undeniable aura that simply can’t be ignored!

What struck me is that while it may take considerable mental resistance to modify such a rare, original car in this way, the time and effort poured into it by its previous owners is truly priceless. You can actively enjoy the extraordinary feel of this classic racer, while also holding onto the ‘ultimate value’ of a car that can always be returned to its original form. This, indeed, is the ‘best and most enjoyable way to experience a classic Mini Cooper S.'”