The carbon work continues to the four doors that weigh a few pounds each while the rear fenders are riveted to the C-pillar and rear bumper. The trunk lid has been cut in order to separate the horizontal panel from the vertical one. The latter has then been made an integral part of the rear structure, and bonded in place to the chassis and rear bumper. So if access to the trunk area is required, only the top part of the lid can be removed. Not good for holding groceries, needless to say. Inside the trunk lives the fuel system, which is comprised of a tiny Wiseco racing fuel tank and Bosch fuel pumps, all neatly aligned. Hard to miss is the subframe which has been constructed to take the high levels of aerodynamic loads that the rear wing generates. Unlike on streetcars, the loads are directly transmitted to the chassis rather then to a body panel like the trunk lid.
The piece de resistance is the 560 PS, 65 kgf-m 2.3-liter 4G63. This green-topped monster is what propels this lightweight Evo to 54-second laps around Tsukuba and, as the HKS team is hoping, into the 53-second territory sometime this year. At its heart lies a host of prototype one-off components like the counter balanced crankshaft, H-section conrods and nickel-plated forged pistons. The head has been machined to insure optimal breathing while the 272 degrees duration cams make sure the valves stay open enough for the 820cc injectors to spray copious amounts of hi-octane fuel into the combustion chamber. The job of compressing the intake charge is up to the HKS GT3037S turbine, which is managed by the GT-II external wastegate and the EVC boost controller solenoids.
Because keeping an engine like this cool is no easy feat, it has been fitted with a custom oil cooler and a large-core radiator with an air-separator system. Everywhere you look in the CT230R's engine bay there is something to admire. Just take a look at the carbon intake pipe, or the custom exhaust manifold. It has all been put together with extreme care, and it certainly shows. Last but not least is the full titanium exhaust system, which pops out from the rear bumper.
The car's shakedown test at Tsukuba circuit in March proved that everything is working as it should. Taniguchi took a few fast laps to test different suspension set-ups and tire compounds. Even if just practicing, Nob managed to lap in 56 seconds. However, a big question remains: Is there enough there to make the CT230R break into the 53s? We're sure HKS has enough mechanical know-how to build a competent car, and no one is going to doubt Taniguchi's capabilities as a driver. Therefore we know it will set a very fast time, the question is how fast.