At the Frankfurt Motor Show in Germany this week, Lexus will unveil the next generation of its GS 450 hybrid, which will make its debut for the 2013 model year. The biggest news for the new GS hybrid will be a 30 percent across-the-board improvement in fuel economy, which should bump the 450′s overall EPA rating into the 30-mpg range.
Originally introduced in 2007, the GS 450 brought a more fuel-efficient option to Lexus’s large luxury sedan line, netting a combined fuel economy improvement of almost 20 percent over the over the similarly-powered V8. But Lexus left one of parent-company Toyota’s key hybrid fuel-saving strategies on the table, and as the efficiency of the gas-only GS has improved over the last few years, the hybrid variant remained frozen at 23 mpg—diminishing the advantage of springing for the gas-electric.
The Prius and nearly every other Toyota hybrid have a powertrain configuration featuring two electric motors and an Atkinson cycle engine, which reduces energy loss by delaying compression and increasing thermal efficiency. Lexus says the switch to an Atkinson cycle will contribute fuel savings of 12 to 14 percent for 2013. Further efficiency enhancements will come from an update to the second-generation Lexus Hybrid Drive system, decreased motor friction, and an increased regenerative breaking range. The updates are similar those brought in 2010 to the Lexus RX 450h hybrid crossover SUV, which runs on the same Atkinson cycle V6.
The GS 450h has combined output of up to 338 horsepower and can accelerate from 0-60 in 5.6 seconds—which is nearly as impressive as the V8-powered GS 460′s 342-hp and 5.4 second 0-60 time. Pricing for the new hybrid hasn’t been announced, but the previous model sells for nearly $60,000, while the 2011 GS 460 starts at around $5,000 less.