UK outlet CAR Magazine compares the Lexus IS300h against the BMW 320d. A hybrid versus a super efficient diesel, a difficult task to determine which one is a better buy.
The new F30 BMW 320d is powered by a 2.0 liter turbocharged engine that delivers 181 horsepower and 280 lb-ft of torque. The Lexus IS300h delivers 178 horsepower and 163 lb-ft of torque from the conventional 2.5 liter engine, and additional 141 hp from the electric motor.
So who takes the win in this unique comparison? Let’s have a look.
Moving on swiftly then to the IS that’s worth reading about, we come to the IS300h. For a surprisingly modest £3k premium over the £26,495 IS250, you get a 2.5-litre Atkinson-cycle naturally-aspirated four, pushing out 178bhp and 163lb ft of the turny stuff, plus a 141bhp electric motor. The combined power figure is a slightly less impressive 220bhp, but that still trumps the 181bhp of the 320d. Trouble is, the 300h’s chunky 1680kg girth – a huge 175kg paunchier than the BMW – and tardy step-off means it never feels as instantly rapid as the German.
Zero to 62mph takes 8.3sec in the IS, but only 7.4sec in the BMW, a pretty spectacular feat given that diesels are much better suited to flexibility measures than outright sprinting. Snap the throttle open and the 320d’s 280lb ft of torque means it’s always the BMW that’s quicker to respond. Work the IS’s engine a little harder though and it’s actually pretty lively, easily capable of keeping pace with the BMW, which runs out of steam at higher revs.
But accessing that top-end performance means a headache of high revs courtesy of the CVT transmission. Keeping the engine spinning continuously at the optimum revs may be good for power and efficiency, but it makes for a strangely disconnected driving experience, at least in something purporting to be a sporting car. Even the IS’s assistant chief engineer admits he doesn’t like it, and claims to be working on a conventional automatic gearbox alternative. For now though, a CVT is not only the most efficient transmission at present, but the only one compact enough to work between the IS’s petrol engine and electric motor.