Chevrolet reveals customer racing GT3.R
Chevrolet’s first GT3 car, the new Corvette Z06 GT3.R, has made its public debut at Daytona International Speedway ahead of the Rolex 24.
The new car is destined for competition in both IMSA and the FIA WEC. The latter will move from the current GTE regulations to the global GT3 platform beginning in 2024. Chevrolet Motorsports will also be evaluating opportunities to be represented in SRO Motorsports including SRO America and the Intercontinental GT Challenge.
Design and development of the mid-engine Z06 GT3.R has been a collaboration between GM’s Competition Motorsports Engineering division and Pratt Miller Engineering.
Based on the mid-engine Chevrolet Corvette Z06 supercar, the new race car takes the level of technology transfer between racing and production to a new level with more shared components and features.
The Z06 GT3.R begun its life as an aluminium chassis frame from Chevrolet’s Bowling Green Assembly plant in Kentucky. At Pratt Miller a purpose-built steel roll cage was welded onto a base plate, which was secured to the chassis. The car has double-wishbone suspension front and rear, Motorsports engineers worked with the GM Design Studio to develop an aero package specific to the Z06 GT3.R to optimize levels of downforce, stability, drag reduction and cooling. The goal was to design a GT3-spec Corvette that is suitable across different tyre specifications, balance-of-performance settings and other customer preferences while not sacrificing performance or drivability on a variety of tracks and racing surfaces.
The car features a carbon fibre splitter and diffuser. Intakes at the front of the Z06 GT3.R draw in air to cool the front brakes. A single, large opening on the hood – a new design philosophy from the C8.R – extracts air after it moves over the radiator. Side air ducts behind the doors – directly inspired by Z06 production road car – help to cool the engine, transaxle and rear brakes.
“The Corvette Z06 GT3.R breaks new ground for Chevrolet and the Corvette Racing program,” said Mark Stielow, director, GM Motorsports Engineering Competition. “This customer-focused racecar leverages learnings from throughout Corvette Racing’s lengthy and successful history, plus the expertise of our Corvette production design, engineering and powertrain teams.”
The Corvette Z06 GT3.R will feature a 5.5-litre, flat-plane crankshaft DOHC V8 engine derived from the production Z06. This engine began on-track development in 2019 with the initial testing of the C8.R, ahead of its use in the production Z06.
The LT6 engine for the GT3.R originates from the Performance Build Center in Bowling Green, the same line on which all production Corvette Z06 engines are built. The powerplant shares more than 70% of its parts with the production Z06 engine, including the crankshaft, connecting rods, cylinder heads, fuel injectors, coils, gaskets and a variety of other sensors.
“Racing continues to play a key role in the development of our production engines,” said Russ O’Blenes, director, Performance and Racing Propulsion Team. “There were valuable lessons learned during the C5-R through C7.R programs that aided in the development of our V8 engines for production and racing – many dealing with efficiency, materials and light-weighting.”
Chevrolet and Pratt Miller have worked together to incorporate a number of features into the GT3.R, building on safety construction from the C8.R. The Z06 GT3 features a side-impact crash structure between the driver’s side door and roll cage. Pioneered in the C7.R, the box features an outer casing of carbon fibre and Kevlar, and is filled with an aluminium honeycomb construction.
The GT3 Corvette’s integrated steel roll cage is slightly modified from the current racing Corvette to provide easier ingress and egress.
The reveal of the Z06 GT3.R follows a two-year testing programme. Virtual simulation through Chevrolet’s Driver in the Loop simulator began in early 2021.
The first on-track test of the Z06 GT3.R took place in September 2022.
The Z06 GT3.R is the latest in a line of championship-winning Corvette race cars that date back to the late 1990s and the introduction of Corvette Racing and the Corvette C5-R. Entering its 25th season, the program has scored 122 race victories around the world, including 113 in IMSA competition.
Those wins have led to 14 Manufacturers’ and Drivers’ championships and 15 Team titles. No team in IMSA history has won more races or championships than Corvette Racing in that span.