The twin turbos operated in sequential mode, not parallel. Initially, all of the exhaust is routed to the first turbine for reduced lag. This resulted in boost and enhanced torque as early as 1800 rpm, where it already produced 300 lb·ft (410 N·m) of torque. At 3500 rpm, some of the exhaust is routed to the second turbine for a "pre-boost" mode, although none of the compressor output is used by the engine at this point. At 4000 rpm, the second turbo's output is used to augment the first turbo's output. Compared to the parallel mode, sequential mode turbos provide quicker low RPM response and increased high RPM boost. This high RPM boost was also aided with technology originally present in the 7M-GE in the form of the Acoustic Control Induction System (ACIS) which is a way of managing the air compression pulses within the intake piping as to increase power.
For this generation, the Supra received a new 6-speed Getrag/Toyota V160 gearbox on the turbo models while the naturally aspirated models made do with a 5-speed manual W58, revised from the previous version. Each model was offered with a 4-speed automatic with manual shifting mode. Turbo models were equipped with larger brakes and tires. All vehicles were equipped with 5-spoke aluminium alloy wheels and a space saver spare tire on a steel wheel to save weight and space.
Toyota took measures to reduce the weight of this new model. Aluminium was used for the hood, targa top (when fitted), front crossmember, oil and transmission pans, and the suspension upper A-arms. Other measures included hollow carpet fibers, magnesium-alloy steering wheel, plastic gas tank and lid, gas injected rear spoiler, and a single pipe exhaust. Despite having more features such as dual airbags, traction control, larger brakes, wheels, tires, and an additional turbo, the car was at least 200 lb (91 kg) lighter than its predecessor. The base model with a manual transmission had a curb weight of 3,210 lb (1,460 kg). The Sport Roof added 40 lb (18 kg) while the automatic transmission added 55 lb (25 kg). It had a 51:49 (front:rear) weight distribution. The turbo model weighed 3,450 lb (1,560 kg) for the manual, automatic added another 10 lb (4.5 kg). Weight distribution was 53% front/47% rear. The Supra was heavier than the spartan Mazda RX-7 and all aluminium bodied Acura/Honda NSX, but it was lighter than the Nissan 300ZX and Mitsubishi 3000GT VR-4.
For the 1996 model year in the US, the turbo model was only available with the automatic transmission owing to OBD-II certification requirements. The targa roof was also made standard on all turbo models. For 1997, manual transmission returned for the optional engine along with a redesign of the tail lights, headlights, front fascia, chromed wheels, and other minor changes such as the radio and steering wheel designs. All 1997 models included badges indicating "Limited Edition 15th Anniversary". All turbo models came standard with the rear spoiler. For 1998, updates were a 3-spoke steerin
g wheel and redesigned radio. In Japan, the turbo engines were installed with VVT-i. The SZ-R model was also updated with the introduction of a six-speed Getrag V161 transmission, the same used for the twin-turbo RZ models.
The stock Mark IV Supra chassis has also proven an effective platform for roadracing, with several top 20 and top 10 One Lap Of America finishes in the SSGT1 class. Despite its curb weight, in 1994 the Mark IV managed remarkable skidpad ratings of 0.95 lateral g's (200 ft) and 0.98 lateral g's (300 ft) The Mark IV Supra also featured a four-sensor four-channel track tuned ABS system with yaw control whereby each caliper is sensored and the brakes are controlled individually according to the speed, angle, and pitch of the approaching corner. This unique Formula One-inspired braking system allowed the Supra Turbo to record a 70 mph (113 km/h) -0 braking distance of 149 ft (45 m), the best braking performance of any production car tested in 1997 by Car and Driver magazine. This record was finally broken in 2004 by a Porsche Carrera GT, which does it in 145 ft (44 m) .
The US and UK market Supra featured bigger injectors, steel turbines and bigger inlet cam and had emissions in the range of 259 g/km CO2 despite the addition of Exhaust Gas Recirculation (EGR). The Japanese market Supra had CO2 emissions in the range of 224 g/km.
By the late 90s, sales of all sporty coupes were declining in North America, so the Supra was withdrawn from the Canadian market in 1996 and the US in 1998. The Turbo was not available in 1998 in California Air Resources Board (CARB) states. Production continued in Japan until August 2002, ceasing owing to restrictive emission standards.
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