Lexus GS450h

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Engineers are kids at heart just like everyone else, and it's only a matter of time before even the most pragmatic of technological advances finds a use in play. Even the hybrid-electric propulsion system, first introduced to the world by Honda's ultra-efficient Insight, has found its way into the hands of the gearheads, and they seem to be enjoying their new toy.

The Lexus GS450h is the hybrid that has all of the "greenies" up in arms, and not in a good way. Why? Because the GS450h's fuel-saving hybrid-electric powertrain isn't entirely about fuel economy. The GS450h is the first hybrid to capitalize primarily on the electric motor's ability to provide instantaneous torque for acceleration. Don't get us wrong, the fuel economy is better than anything else in its class, but it's more of a pleasant side effect to the performance boost. Fuel economy is 25/28. That's average for the industry, but fantastic compared to the GS450h's V8-powered competitors, who struggle to make 20 mpg.
 

Lexus says the GS450h's performance rivals that of a Porsche 911, and it easily beats most of its V8-powered competitors. We're inclined to agree. The GS450h is the first rear-wheel drive hybrid, and its 3.5 liter V6 is attached to a 180 horsepower motor-generator that doubles as the transmission. The gas engine uses a conventional Otto combustion cycle instead of the more efficient Atkinson-cycle used by many hybrids, and makes 292 horsepower. A flexible dual fuel injection system is similar to that in the IS350 and allows the GS450h to burn fuel more completely. Total horsepower varies depending on the speed of the two electric motor-generators, but Lexus places the figure at 339 horsepower. The magic of the electric motor-generator, and its interest to enthusiasts, of course, is instant torque. This big car definitely has the power to get up and scoot, although we'd argue that it might be somewhat less entertaining than a Porsche.

Hit the gas and the GS450h offers a generous shove to the backside that any V8 driver will recognize, but without the same throaty engine note. On the road, the first thing we noticed when we put our foot down actually wasn't the powerful acceleration, but the strange engine note. The GS450h doesn't roar like a V8; it's got a V6 whine. It's not a bad thing; buyers who want V8 rumble and drama can get the (slower) GS430. This car is very, very quick when given the boot. It's also a full hybrid, which means that it can run on naught but electricity when necessary.

Also affecting the GS450h's performance sound is the transmission which, like the gearbox in the Prius, isn't exactly a "gearbox" per se. The electronic continuously variable transmission (ECVT) shifts without apparent breaks between gears. A two-stage torque multiplication system allows GS450h drivers to select between three modes, just like in a standard automatic transmission; normal, power and snow. The ECVT is stepped to mimic the automatics used in other sport sedans too, and offers lag-free downshifts to lower ratios that drastically improve acceleration.

Handling hasn't been affected; with all that power, Lexus has done a good job of keeping the car from losing any performance ability. The GS450h's battery pack is located between the trunk and rear seat. It weighs 132 pounds, and we could sometimes feel the extra weight back there during rapid transitions on curvy roads. The GS450h nonetheless maintains a high level of grip and confidence. Lexus' Vehicle Dynamics Integrated Management (VDIM) is standard on the GS450h. VDIM integrates a host of systems, including the electric power steering, antilock brakes and vehicle stability control, and offers almost intuitive handling adjustments to keep the GS450h under control.

From the outside, the newest addition to the GS family has the same strong-shouldered, muscular design as the rest of its siblings. A chrome strip that runs along the rocker panels like a running board is a handsome touch that looks good on dark-colored cars. Eighteen-inch wheels are standard.

From the driver's seat, there's almost nothing to set the GS450h apart from the rest of the Lexus lineup. Sharp eyes will notice that the tachometer has been replaced by a kilowatts gauge, and that's about it. This car screams "luxury," not "economy." The brushed-metal gauge faces and handsome, clean interior are unchanged from the conventionally-powered GS. There's leather seating all around, naturally, and a choice of walnut or birds-eye maple wood trim. Heated and cooled front seats, a tire pressure monitoring system, and "adaptive" front lighting that turns with the front wheels are on the standard equipment list, too. Maneuvering in town is aided by a rear backup camera and ultrasonic parking assist. Bluetooth wireless phone capability makes this a good executive transportation device.

This car is a good example of what happens when the engineering types take the latest technology and go a little crazy with it. The Lexus GS450h my pack a fuel-saving drivetrain under the hood, but its forte is all-out performance. The harder question is this; why would one take the $3500 price walk from the V8-powered, 18/25 mpg GS430 to the 25/28 GS450h? Four or five miles per gallon is a decent savings, but it'll be quite a long time before the GS450h pays off its $54,900 sticker price in fuel savings. The performance is impressive, but many gearheads may find it uninspiring due to a lack of aural grace--the GS450h just doesn't sound like it's having fun, no matter how quickly the miles are ticking past.


Specifications:

All specs are for the 2007 Lexus GS450h.
Length: 190.0 in.
Width: 71.7 in.
Height: 56.1 in.
Wheelbase: 112.2 in.,
Curb weight: 4134 lb.
Cargo space: 7.5 cu.ft.
Base price: $54,900
Engine: 3.5 liter DOHC 24-valve V6 + two permanent magnet electric motor-generators
Drivetrain: electronic continuously variable transmission, rear-wheel drive
Horsepower: 339 (combined)
Torque: 267 @ 4800 (gas engine)
Fuel capacity: 17.2 gal.
Est. mileage: 25/28