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It has been a little over seven months since Toyota first unveiled the GR GT, its forthcoming sports car developed with the near single-minded aim of winning races in GR GT3 specification. Since that first official reveal, only a limited number of details have emerged, so a press briefing at WeatherTech Raceway Laguna Seca during the Rolex Monterey Historics at Monterey Car Week offered a useful opportunity to learn more about the car’s powertrain and structure.

To begin with, there was a static model of the complete car on display. Seen in person, the GR GT is far more dramatic than pictures suggest. The bonnet appears extraordinarily long, while the flanks look remarkably flat. All of that is in aid of the race car’s aerodynamic needs, because the silhouette of the road-going version and the competition model is almost identical. Toyota representatives say 80 percent of the GT3 version is shared with the road car, which means this is far more than a simple silhouette racer.

From an aerodynamic standpoint, not needing wider front or rear fenders helps keep turbulence down and reduces drag. There is also an interesting detail at the rear, where a pair of tabs above the number plate bracket protrude farther than expected. The explanation is that FIA regulations allow the rear wing to be mounted at the rearmost point of the bodywork; in this case, the GR GT3 can use those extra few inches to place the wing further back, increasing the lever arm for the downforce being applied.

Toyota has not yet disclosed exactly where every inlet and vent channels air through the car, but the intake and mesh vents on the bonnet are clear nods to similar design elements on the Lexus LFA, as is the sculpted intake above the rear fenders. Even the outer door latch, a flush panel that pivots inward, echoes the arrangement seen on Toyota’s last supercar.

It is no secret that the GR GT adopts the layout and orientation used by the Mercedes-AMG GT3, with the engine mounted behind the front axle line and a transaxle positioned at the rear. Once again, this is done with the GR GT3’s role in mind, because a long wheelbase with mass concentrated at both ends delivers stable and predictable handling. That is especially useful in many GT3-based series, where classes often include amateur racers. The long bonnet also helps create smoother airflow over the rest of the body.

The most surprising aspect of the powertrain, however, is that it is completely rigid from the crankshaft to the axle shafts, with no bushings or universal joints in between. Power flows straight from the flywheel to the carbon-fibre driveshaft, which itself is enclosed within a carbon-fibre torque tube featuring flat sides for added stiffness, then into the wet-plate clutch pack at the front of the transmission and onward through the gears. At the rear of the transmission, the helical gears are cut so that the output shaft sits at a two-degree angle, just enough to clear the sides of the gearbox and route forward to the mechanical limited-slip differential inside the bellhousing without needing a universal joint. In real-world terms, that should make both the GR GT and the GT3 exceptionally responsive.

Another noteworthy element inside the gearbox is a small gear-driven oil pump packaged close to the differential. Because of where it is placed, it rotates in direct proportion to rear wheel speed rather than operating on a shared circuit with other components.

The hybrid motor, equipped with its own clutch pack, is mounted at the front of the transmission alongside the wet-plate clutch. It functions as the starter and alternator, and it also powers accessories such as the power steering and air conditioning. It is also responsible for moving the GR GT backwards when required, by spinning in reverse while first gear is engaged; there is no conventional reverse gear ratio in the gearbox. Perhaps most importantly, the electric motor also helps damp engine vibrations and enables quicker shifts.

During the briefing, a Toyota representative said the 40 horsepower produced by the hybrid motor is “less than five percent of the total power”, which strongly suggests the quoted 641 horsepower figure for the engine will rise, most likely through higher-performance variants introduced during the car’s lifecycle. After all, 40 horsepower is more than 6 percent of the current figure, while 5 percent would imply 800 hp or more. There is another clue in the engine’s G40E designation, which places it in the same family as the G16E three-cylinder used in the GR Corolla and GR Yaris, as well as the G20E previewed in the mid-engine GR Yaris M Concept and likely destined for an upcoming mid-engine sports car. Those smaller G-family engines are capable of at least 100 hp per cylinder.

Returning to the engine itself, Toyota’s objective was to mount it low and as far rearward as possible. The absence of a conventional accessory drive, since those functions are handled by the hybrid system, helps keep the engine’s length down, while a dry-sump oil system allows it to sit lower in the chassis. The oil circuit uses large hoses connected to a massive oil reservoir located behind the front passenger-side wheel, and a pair of IHI turbochargers mounted within the vee feed 16 pounds of boost into the 4.0-litre V-8. The relatively long timing chains visible in the chassis cutaway suggest the engine may not rev as freely as the 8000-plus rpm engines used by Chevrolet, Ferrari, Lamborghini and Porsche in the road-going counterparts to their GT3 race cars. Even so, if the previously hinted power increases do materialise, the GR GT should still offer a competitive weight-to-power ratio against its rivals.

Finally, there is the chassis. Toyota uses four extremely large castings, one at each corner, to mount both the suspension and the powertrain, reinforcing the broader theme of structural rigidity seen in the engine and transmission. The suspension mounts are designed to shear away in an impact while leaving the castings intact. The suspension layout itself is fairly conventional, using double wishbones at the front and rear, with additional lateral links at the rear. The coilover springs feature an adjustable perch, presumably allowing owners to fine-tune ride height and overall rake to suit personal preference or the demands of their home circuit.

The GR GT3 race car is expected to arrive in the United States in IMSA sometime after the beginning of the 2027 season, while deliveries of the GR GT road car are likely to begin towards the end of next year. More details are still awaited, but from a technical perspective, the GR GT continues to look every bit as promising as its tiny luggage compartment appears impractical.