Lexus formally unveiled the 2007 GS 450h sedan at the 2005 New York Auto Show. Like the RX 400h sport utility vehicle, the GS 450h emphasizes performance over fuel efficiency. To that end, its gasoline engine and hybrid motors combine to make 339 horsepower, a healthy gain over the 300-hp GS 430. Lexus says the GS 450h can accelerate from zero to 60 mph in 5.2 seconds, making it both the quickest Lexus and the quickest hybrid vehicle on sale today.
Rated at a combined 26 mpg by the Environmental Protection Agency, the GS 450h sips gas on par with the V-6-powered GS 300. There's a more compelling case when it's compared to the V-8-equipped GS 430, which has a significantly worse combined estimate (21 mpg) and slower straight-line performance (5.7 seconds from zero to 60, Lexus says). The 2007 GS 450h is also priced less than $1,500 above a similarly equipped 2006 GS 430. In the realm of hybrids, that's a very low premium.
GS 450h sedans hit showrooms in early May. As the performance leader in the GS lineup, it competes with heavy hitters like the BMW 550i, Cadillac STS V-8 and Infiniti M45.
Virtually identical to the GS 300 and GS 430 sedans, the GS 450h sports Lexus' now-familiar face with its steeply raked headlights and thick C-pillars. An adaptive suspension continually senses road conditions to modify damping appropriately. A Sport mode incorporates tighter damping, and an optional active stabilizer mitigates body roll even more.
Several features that are optional on other GS sedans are standard on the GS 450h, including a moonroof, rear park assist and rain-sensing windshield wipers. Eighteen-inch wheels wear P245/40R18 tires. An all-wheel-drive variant, available in the GS 300 lineup, is not offered for the GS 450h.
An electric-power meter replaces the tachometer in the leftmost instrument pod, while a dashboard information screen displays energy consumption statistics and an animation of real-time power routing. Otherwise, the GS 450h's interior is identical to other GS models. Leather seats are heated, ventilated and power-adjustable up front, and dual-zone automatic climate control, an electric rear sunshade and a 10-speaker audio system are standard.
Additional sound dampening and an acoustically tuned windshield are installed. Options include a navigation system and a 14-speaker audio system. Due to intrusion from the hybrid system's two battery packs, trunk volume shrinks from 12.7 cubic feet in non-hybrid GS models to 7.5 cubic feet in the GS 450h.
The GS 450h's direct-injection, 3.5-liter V-6 engine is shared with Lexus' smaller IS 350 sedan. It makes 292 hp in the GS and teams with two electric motors — one providing power during startup, the other boosting acceleration — for a combined 339 hp. Other hybrid traits include regenerative braking, engine shutoff at standstills and the ability to move solely on electric power during light-load situations. A continuously variable transmission is standard.
Lexus does not calculate total torque for the gasoline/electric hybrid system, but given that the GS 450h accelerates markedly quicker than the GS 430 (which has 325 pounds-feet of torque), total torque is likely much higher than the 267 pounds-feet the V-6 engine alone makes.
A full complement of electronic safety features centers around Lexus' Vehicle Dynamics Integrated Management system, which is standard. VDIM coordinates the electronic stability system, antilock brakes, electronic steering and electronic brakes to aid driver control. Optional adaptive cruise control can sense impending collisions and alert the driver. Front knee airbags, side-impact airbags and side curtain-type airbags are standard.