It takes some degree of bravery by a car company to put up its latest car against the vehicle it replaces.
After all, the new car should embarrass the old one which means you are denigrating your own product. But, that's just what Lexus did at the Australian launch of the all-new 2009 RX450h h standing for hybrid. We were able to road test the new against the old at Sydney's Eastern Creek race track, both on the track and sliding around a skid pan.
Lexus was keen for us to experience the difference between the new RX450h and the SUV it replaces, the RX400h. Lexus had little to lose. The RX450h is Robinson Crusoe in the luxury SUV segment, pitted against a raft of diesel-powered vehicles. And, in any case, there was not too much too wrong with the RX400h.
The RX450h is clearly a generation ahead the aspects you discover on the skid pan and track which are primarily handling, braking and passenger comfort when the car is pushed to the limit. On road, the difference is marked also. But here we found out that difference is a real-world, hip-pocket one: economy. Now using an Atkinson cycle engine the second generation RX hybrid is capable of fuel economy of 6.4 litres/100 kms. That's not quite in Prius country, but is certainly in the same ball park as small, four cylinder cars. And it's well under the already impressive 8.1 litres/100 km achieved by the RX400h. At the other end of the scale this three engined-SUV that weighs more than two tonnes, has the power of a V8 but low emissions.
The RX450h was built from ground-up to be a hybrid, said Lexus Australia chief executive, John Roca. Hybrid is now mainstream technology well beyond diesel and in this area Lexus is a leader, he said. The RX450h incorporates a number of changes in the car which has itself for apples v. apples competition. What has not changed is the unique configuration. A 3.5 litre V6 petrol engine driving the front wheels, along with a 123 kW/335Nm electric motor, and a 50kW/139Nm electric motor to power the rear wheels.
The two electric motors have slightly increased power, while the petrol engine is an all-new affair using Atkinson cycle to achieve 183kW at 6000 rpm and maximum torque of 317 Nm at 4800 rpm. The combined system output of 220 kW gives it significant grunt. The RX450h motors to 100 km/h in just 7.8 seconds, which will see many a car off at the lights. In our road test were were able to achieve 7.4 litres/100 kms, but this soon jumped to 7.9 litres/100kms as we headed into the steep Blue Mountains foothills.
We have no doubt 6.4 litres/100 km is achievable given relatively flat roads and a moderate driving style. In fact the RX450h is Australia's first hybrid vehicle to be exempt from the Federal Government's LCT (Luxury Car Tax). The car set an official 6.4 litres/100kms to come well under the 7.0 litres/100 km cut-off. This exemption equates to more than $4000 enabling the hybrid to enter the market at just under $90,000.
The RX450h was tested to death literally. It was subjected to 233 actual tests in a $30 million test program. And, that doesn't include the cost of the cars demolished. It now features 10 airbags, up from seven in the RX400h. According to Mr Roca the RX450h, in a single year of motoring, will save the same amount of carbon emitted from eight return flights from Melbourne to Sydney.
Put another way the RX450h will emit almost 1.6 tonnes less CO2 than the petrol-powered Lexus RX350, and significantly less than it's diesel-powered rivals. The RX450h will have a three model line-up (unlike RX450h that had one, Sports Luxury) which will be Prestige ($89,900) Sports ($96,900) and Sports Luxury ($107,900). These are RRP prices only and do not include State Government charges or delivery costs, which vary from state to state.
FIRST DRIVING IMPRESSIONS
The Atkinson cycle engine seems to be quieter than the engine it replaces and this leads to better NVH, (noise, vibration, harshness) and leads to less noise intrusion into the cabin. Power is run through a CVT transmission which is seamless, but still retains some of the over-revving-slipping feeling that is inherent in these gearboxes but that's only when you plant the right foot.
The real differences in driving feel between the two vehicles is in ride and handling. Built on a new, stiffer, chassis, and with a new suspension, the ride is flatter and smoother under hard cornering. It lacks the dull feeling you get with some hybrids. The rear suspension has made the changes possible and features a trailing-arm type double-wishbone arrangement. This system also allows for the coil springs and dampers to be set below the floor, adding increased luggage space.
The car sits on a lower centre of gravity, and has a 25mm longer wheel base and wider track front and rear. This is all fine-tuning from the previous model and adds up to a better handling vehicle. The front suspension spring rates have been revised along with other improvements related to durability. There is a lot less spring in the front, noticeable under heavy braking, which gives the vehicle a lot more stability.
The vehicle's cabin has been given a full makeover with a strong theme of `display' and `operation' giving the driver easy access to information and a comfortable and easy use of the car's various functions. Lexus RX450h goes on sale on July 13 and orders have already been taken for the first three months allocation of 60 cars a month, mostly from Lexus RX350 owners.
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