Subaru has built its own 911 GT3 and GT3 Touring. Not literally – about the only thing the evocatively-named BRZ STI Sport Type RA shares with the Porsche is a boxer engine layout.

But the parallels in philosophy are unmistakable: take a pure driver's car, sprinkle it with genuine motorsport provenance, forget headline-grabbing power figures and make incremental gains via precision engineered parts adding up to a greater whole, then produce it in strictly limited numbers. It's the sort of car Andreas Preuninger might skunkwork if he ever decided to start a development consultancy.

Unlike his Zuffenhausen bread and butter, the Subaru is only demanding £28,000 (at current exchange rates) rather than the £170,000 (plus dealer taxes) a GT3 commands. And nor do you have to be a member of the Dealer Principal's Saturday morning fourball in order to get an allocation – although you do literally have to be a lottery winner, as all 300 examples will be raffled off to those in Japan who register interest. Yes, sadly that means the RA is yet another forbidden JDM fruit.

But what we can celebrate is a manufacturer in 2025 taking a rather old school view to engine tuning, for the RA remains naturally aspirated. Embossed with the words "Balanced Boxer", the flat-four’s swept capacity remains at 2.4 litres, yet the FA24 has been comprehensively reworked internally. Subaru has achieved a 50 per cent reduction in weight tolerance for the pistons and connecting rods, meaning individual components across the production run match far more closely than in standard manufacturing. 

The crankshaft also benefits from an 80 per cent reduction in rotational balance tolerance. Subaru Technica International isn't making any power claims, but tighter tolerances should fundamentally alter how the engine operates. Less energy is wasted managing imbalance, parasitic vibration is reduced, and the reciprocating assembly works in greater harmony, addressing a longstanding criticism of the 86/BRZ twins: that the engine never felt as sweet or responsive as the chassis.

The precision milling doesn’t stop there – the flywheel drops 67 per cent of its weight compared to standard, while the clutch cover sheds 50 per cent. The result, according to Subaru, is a powertrain that revs more willingly and delivers a character noticeably closer to the racing unit used in Super Taikyu Series competition. It's a serious investment for just 300 units.

The chassis receives similar attention. All four corners benefit from bespoke ZF dampers, developed using Super Taikyu data. Upgraded Brembo brakes also feature, with gold-painted calipers, though equally significant improvements lie beyond this nod to tradition. The rear differential, for instance, gains additional cooling fins after Super Taikyu data revealed thermal management as the limiting factor during race stints. Most RA owners will never push the car hard enough or long enough to benefit, but that's missing the point – the modification exists because the competition data demanded it, not because of a marketing meeting.

Chassis stiffening, revised anti-roll bars, and a bespoke underbody aero package complete the mechanical changes. Forged BBS wheels – finished in bronze for the winged versions, and gunmetal for the wingless – reduce unsprung mass, while flexible V-bands replace conventional exhaust clamps. Not all the revisions are hardware based though, for the RA also adds a flat-shift function to the existing rev-matching of the road car.

Subaru's approach here mirrors what engineering partner Toyota has been doing with special JDM Gazoo Racing variants of the GR Yaris. The Mazda MX-5 Spirit 12R has also been developed using a similar mindset. The trio are a throwback to the lost art of frustrated engineers looking for ways around the 276bhp power cap of the 1990s… an intercooler spray here, a revised rear wing there. Incremental improvements adding up to something greater than the sum of their parts.

While the GT3 reference may be tongue-in-cheek, with only 300 examples confirmed for production – 200 sans wing, 100 sporting – the likely reality is such artificial scarcity will inflate future collector values. We've seen it all before with S204s, Spec Cs, and NISMO GT-Rs trading at multiples of their original value.

Regardless of the inevitable, the one thing the BRZ STI Sport Type RA demonstrates is developing naturally aspirated cars still has merit in 2025, creating a car worthy of a place in any lottery winners’ garage.