Car Design News: Toyota TRD Aurion In Depth (AU)

Wednesday, January 23, 2008

Toyota TRD Aurion In Depth (AU)

TRD AURION ENGINE BALANCES PERFORMANCE AND ECONOMY

New TRD Aurion has a supercharged engine for the best balance of performance, driveability and economy. TRD chose supercharging over turbocharging for the new performance Aurion to optimise throttle response and torque. It is the first original equipment (OE) application in the world for the new four-lobe Eaton TVS (Twin Vortices Series) supercharger.

TRD Aurion's supercharged 3.5-litre dual-VVT-i Quad Cam 2GR-FE V6 engine delivers 241kW of power at 6400rpm and 400Nm of torque at 4000rpm, on 98-octane premium unleaded petrol. The supercharged engine has more than 300Nm of torque available from 1250rpm through to redline. It is matched to an intelligent six-speed automatic transmission with sequential shift. The supercharged engine gives TRD Aurion 0-100km/h acceleration of 6.1 seconds and standing 400m acceleration of 14.2 seconds. The vehicle has been tested for fuel economy to the ADR81/01 standard, returning 10.9 litres/100km* on the combined cycle.

TRD Aurion has been developed and tested to meet Toyota original equipment quality, durability and reliability (QDR) standards. It has been subjected to testing in extreme heat and cold, as well as a 100-hour dynamometer maximum load test and 10,000km V-max test.

*Fuel consumption will vary depending on driving conditions/style, vehicle conditions and options/accessories. Source of fuel consumption data: ADR81/01 combined cycle.

TRD CHOOSES SUPERCHARGER FOR PERFORMANCE AURION

New TRD Aurion is Toyota's first supercharged model in Australia. TRD chose supercharging over turbocharging to achieve instantaneous engine response and impressive low-down torque. At just 1800rpm, the supercharged TRD Aurion engine matches the 336Nm peak torque of the naturally aspirated Aurion engine. TRD Aurion's Eaton TVS supercharger is driven by a V-belt, off the engine's crankshaft.

According to a Toyota Australia survey conducted in 2001 using vehicles with data loggers, Australian driving preferences are unique. Australian drivers want instantaneous response and low-down torque - to accelerate briskly to the speed limit like Americans. But they also want to brake late into corners and maintain corner speed, like European drivers.

TRD worked with leading Melbourne-based motorsport engineering company Harrop Engineering Australia on supercharger development. Harrop is one of only two Eaton agents worldwide. Its applications engineering role in the TRD Aurion engine development included supercharger selection, design and casting of the supercharger casing and inlet manifold, and design of the drive-belt pulleys. It also carried out the finite element analysis for stress in the engine and airflow analysis. TRD's guidelines in the supercharged engine development included retaining the original equipment Aurion fuel rail and minimising the number of unique service tools.

TRD AURION HAS NEW EATON TVS SUPERCHARGER

TRD Aurion is the first OE vehicle to feature Eaton's new-generation four-lobe supercharger technology. It has the new Eaton TVS (Twin Vortices System) supercharger. The new four-lobe rotor Eaton TVS design offers significant advantages over three-lobe supercharger designs. Its key benefit is greater thermal efficiency, which results in a lower inlet manifold temperature, improved charge density and increased performance.

Other benefits include a higher pressure ratio, increased airflow capacity for the same supercharger package size, increased operating range (rpm), higher efficiency and quieter operation, improved fuel economy at cruising speeds and instantaneous boost response. The four lobes have 160 degrees of twist over their length, compared with 60 degrees in Eaton's current three-lobe supercharger designs. The large lobe twist allows for a larger inlet port, improved airflow and a larger useable outlet port area. The supercharger installation in TRD Aurion includes a specially developed sports muffler, with a 15 per cent reduction in back pressure compared with the OE Aurion muffler. The muffler has been tuned for a sporty note while maintaining acceptable drive-by noise levels. Development of the supercharged 2GR-FE engine has resulted in a unique engine calibration. It is Toyota Australia's first in-house engine calibration.

This includes:

fast throttle response, achieved by power enrichment and TRD pedal mapping;
Euro IV emissions compliance, achieved by OE fuelling strategy at cruising speeds;
low fuel consumption by using 98 RON fuel with active knock control.