Drift Tengoku — September 2004 · Page 298

The change from an actuator-controlled GT30 Pro turbo to an external-wastegate GT3037S came in April of the previous year. D1 was beginning to demand not just speed but smoke, angle, exhaust sound and other forms of impact, so the external-wastegate setup was chosen for its stronger presence. Turbo capacity increased, raising output from 420 to 490 hp; regulations requiring a catalytic converter ultimately brought it to 470 hp.

Although the turbo emphasizes high rpm, combining it with HKS V-Cam produces strong acceleration from low revs. Particular care is taken over the engine bay's appearance so it stays ready for a show. Bolts securing fenders, lights and cooling panels use lightweight titanium or duralumin.

Ueno's commitment to beauty should be clear from…

Carbon panels cover the floor and a diffuser is fitted at the rear. Aerodynamic performance matters more here than floor protection. The front panel also aids cooling: removing it experimentally made coolant temperature rise more easily and even affected engine feel. The rear diffuser was designed with Tsukuba's Super Lap in mind. Both are carbon, held by turnbuckle-type stays that allow fine adjustment of their positions…

The front anti-roll bar is hydraulically adjustable from the cabin. Its effect and alignment are fine-tuned to conditions, but changes are seldom made at the circuit; most work is done carefully on the alignment tester at Sweeper, T&E's technical shop. Alignment usually stays within factory reference ranges, without unusual settings.

Ueno contributed much of the setup work for the retail Soarer Hipermax suspension, but this car uses revised damping and spring rates for its weight. At Ebisu, the front spring rate was 16 kg/mm.

Ueno says moving toward mild behavior rather than abrupt reactions was the right choice. The arms use Ikeya Formula pillow-ball parts, but damping is relatively soft for the specification, allowing the car to retain angle when the throttle is released. Allowing the body to roll broadens the control range and makes use of rear-end inertia.

Initial LSD torque is a high 14 kg·m, chosen with S-tire time attacks in mind; it also gives good traction during drifting. The final-drive ratio changed from 3.2 at Sugo to 3.9 at Ebisu. The rear spring rate at Ebisu was 14 kg/mm.