Another big weekend for Toyota in Thailand, as the carmaker will once again be fielding entrants in the annual Idemitsu Super Endurance Southeast Asia Trophy 2023 10-hour race that takes place on 23-December 2023 at the Chang International Circuit in Buriram.

Just like last year, the Toyota cars entering are split between the Toyota Gazoo Racing Team Thailand (TGRTT) and ORC Rookie Racing, a privateer team owned by Toyota Motor Corporation's Chairman, Akio Toyoda. Think of TGRTT as the team that races for points, while Rookie Racing puts experimental cars through the wringer to improve them.

As such, Rookie Racing adds a third entrant this year – a Prius GR Concept running on synthetic fuel. Rather just-in-time, first images of it have floated on to the Internet and golly, it looks serious.

Performance figures haven't been officially outlined just yet, though Toyota says this is the first time they race a production Prius. But what about the older Super GT one? That was heavily modified and features a mid-engined chassis, if you remember.

In stock, series-parallel hybrid form, today's 2-litre petrol-electric hybrid Prius has a combined system output of 196 PS. There's a plug-in hybrid variant too with 223 PS, though we can't tell if that is the one making its Buriram rounds this weekend.

Guesses aside, car #264 looks largely standard, save for some minor bodywork updates that serve to save weight and sharpen aerodynamics. There's a carbon-fibre chin splitter and set of wheel arches, canards by the bumper, vented hood (presumably made out of lighter materials, if the pins are a telltale sign), and the most unsubtle spoiler known to a Prius perched at the back.

There also upgraded Endless brakes, customary stripped-out interior with a rollcage, and what seems to be a modified exhaust system as well. Mostly what looks to be regulation safety items.

In any case, it certainly be very interesting to see how the car performs this weekend, and the subsequent improvements we can expect from this experience. The team's hydrogen-burning GR Corolla, for instance, now makes way more power than when it first debuted in 2020.

Also read: Back from the dead, this Toyota GR Corolla made history as world's first liquid hydrogen racer to complete an endurance race

The racetrack proves to be one of Toyota's most valuable 'testing grounds' as it offers a punishing environment unlike most synthetic lab tests, and that is invaluable in vehicle development. Beyond carbon-neutral solutions, the company has also torture-tested the 2023 Toyota Vios' CVT in a 25-hour race last year – and that came back home without any incidents.

Besides the GR Prius Concept, Rookie Racing will also race a hydrogen-burning GR Corolla, as well as a synthetic-fuel GR86. TGRTT will field a Yaris and Corolla Altis with synthetic fuels, as part of their 11-car strong team that also comprises women drivers.

Also read: Most reliable CVT ever? All-new AC100 2023 Toyota Vios held up to 25 hours of endurance racing