Infiniti M35 Hybrid (2011) - Car Review

This is the Infiniti M35 Hybrid, the company’s first hybrid offering. CAR has just been behind the wheel in Japan, and not only has the stint allowed us to test the electrified powertrain, but it’s also our first chance to assess the chances of Infiniti’s new 5-series/E-class/A6 rival.

The new M Line is on sale in America and the UK now with a 3.7-litre V6 engine, but a big saloon/big petrol engine is far from the perfect combination for this side of the Atlantic. Instead the hybrid M (available in early 2011) and a 3.0-litre diesel M (on sale in October 2010) will make up the majority of the Euro sales, 35% and 45% respectively.

Tell us about the hybrid system in this new Infiniti M35 Hybrid…
Bar forthcoming electric/diesel combinations from PSA and Mercedes, every other hybrid mates a petrol powertrain to an electric module, and the Infiniti M35 Hybrid is no different. The set-up utilises Infiniti’s older 3.5-litre V6, doing without the newer 3.7’s variable valve VVEL system that boosts low-down torque because the electric motor takes that job.

The electric motor itself offers up 68bhp and 199lb ft, and with lithium-ion batteries (with a 1.3kWh capacity) allows the M35 Hybrid to cover around 2km in pure EV mode. It can also run solely using the electric motor at speeds up to around 50mph, or 80mph if you’re going downhill with a decent bit of wind behind you. The motor sits between two clutches, one dry clutch that decouples the engine to reduce mechanical loses, and a second wet clutch that’s used to modulate torque fluctuations when the petrol engine restarts on the move.

How does Infiniti's first hybrid juggle the two power supplies?
It's pretty quick. Excluding the 414bhp M56 that won’t come to Europe, the M35 H is the fastest M around, hitting 62mph quicker than either the 37 or 30d. Much more importantly, it’s also cleaner and more efficient that either.

Infiniti won’t release any official figures yet, but it promises it’ll easily best the 179g/km and 37.2mpg achieved by the Lexus GS450h. But while Infiniti claims its system is simpler than that offered by Lexus, and is thus easier to package, the hybrid pack still adds around 120kg and robs boot space, putting its kerbweight and carrying capacity pretty close to the GS450h’s 1930kg and 280 litres.

Press the start button and you get very little response, as the electric motor wakes up but leaves the petrol engine off. Move away and you’ll still be in zero emissions mode, so you can glide out of the office car park with just a whisper, and we consistently found the M35 Hybrid would run in its electric mode up to about 20mph as long as you didn’t accelerate too hard. Beyond that the petrol engine kicks in, and you then run on V6 power, both, or just the e-motor when the petrol engine shuts down at speed. Have both power supplies sending drive to the rear wheels and you’ll find a decently quick car (complete with a nice V6 howl) despite the near-two tonne kerbweight.

A full dynamic assessment will have to wait until we try the M away from the confines of a smooth Japanese test track, but with the hybrid pack this Infiniti feels lumbering and heavy and the steering is relatively light. With the new 5-series so good, the M will have a tough time in a head-to-head.

What about the rest of the Infiniti M Line package?

Infiniti itself admits that it doesn’t expect to steal customers from Mercedes. Instead it’s gunning for BMW, and with the new 5-series so surprisingly conservative the new M looks like a credible alternative.

The interior design might not be to everyone’s tastes – the tiered effect is quite imposing – but it’s well built, easy to use, and there’s loads of space, especially if you want to lounge on the big comfortable seats in the back. Plus just about all the gadgets you’ll be after will be standard, whereas you’ll have to delve into the expensive options list if you want the same kit on your BMW.

Verdict

Only a more thorough drive will really reveal how good the Infiniti M Line really is, but the interior is impressive and the dynamics, while not BMW-sharp, are still good. And if Infiniti’s claims are true, it offers a hybrid powertrain that Lexus can’t match, and the rest of its rivals don’t yet have.

The devil is in the detail, of course, and until Infiniti comes out with its official economy and emissions figures, we have no idea if they're just talking hot air. We suspect they're not, though...

Add in the diesel option and the new M could and should signal the start of more Europeans taking Infiniti seriously.