New Car Reviews

First Drive: 2012 Infiniti M35h Hybrid US Spec

Fuel prices are on the rise again, and so maybe you’re thinking it’s time to downsize your mid-size performance-luxury car. Perhaps something like a Honda Fit. Since you like to make a statement, you’re also looking at the Nissan Cube. The turbocharged Nissan Juke has a bunch more power, so maybe that teensy compact crossover is on the shopping list, too.

Ugh, but downgrading to an entry-level car is just so difficult. Perhaps the MINI Cooper is the way to go-or even better, the John Cooper Works version. It has performance, fuel economy, and a premium sticker. And, like all of the other cars listed, it gets around 30 mpg in the EPA combined testing.

Or you could just buy the new 2012 Infiniti M35h and not downgrade anything. You’ll save just as much fuel. That’s right, at an EPA-estimated 27 mpg city, 32 mpg highway (29 mpg combined), the Infiniti M35h does just as well as the Honda Fit (30 mpg), the Nissan Cube (28 mpg), the Nissan Juke (29 mpg), and the JCW Mini Cooper (28 mpg.)

The Infiniti M35h also has lots of things those little cars don’t: 360 horsepower, for one. A big, roomy back seat, for another. One of the prettiest and most elegant interiors in the business, for a third. But let’s get back to those 360 horses.

The M35’s gasoline engine is a 3.5-liter VQ-series V-6 producing 302 hp and 258 lb-ft of torque. For greater efficiency, it runs on the Atkinson cycle, and it does without the VVEL infinitely variable valve-lift system on the M sedan’s other engines. It’s backed up by a 50-kW (67-hp) electric motor that produces 199 lb-ft of torque.

Sandwiched between the engine and the seven-speed automatic transmission, the motor eliminates the need for a torque converter. It’s powered by a 345-volt, 96-cell battery pack. Using lithium-ion instead of nickel-metal hydride batteries, the 1.4-kWh battery pack weighs only 99 lb.

From the outside, the only indication that this M is a hybrid is from its badges. There are no extra aero aids (although underbody cladding and higher tire pressure reduce the coefficient of drag from 0.27 to 0.26), there are no goofy spoilers, and the tires are the same wide Michelin Primacy MXM4s from the M37 — no skinny, rock-hard, handling-averse low-rolling-resistance tires.

There’s not much of a visual difference from behind the wheel, either. It’s the same gorgeous cabin that’s draped in leather and wood. A charge/assist meter has appeared in the instrument cluster where the coolant temperature gauge once was, and there are some additional lights and displays — but you won’t see an LCD panel with a tree growing leaves while you pretend you’re saving the planet in your hybrid.

The driving experience, too, is largely unchanged, except for the subtleties. First, the M35h is fast — very fast. To our backsides, it’s even quicker than the 330-hp M37 (which makes sense, given its slightly more favorable power-to-weight ratio) despite using the considerably longer final-drive ratio from the V-8-powered M56. Speaking of the 420-hp M56: thanks to the electric motor’s massive torque, the M35h squirts off the line more quickly than it does. We suspect that, in an all-out drag race, the V-8 would eventually pull ahead, but the hybrid M feels just as powerful around town.

As usual, Nissan’s VQ isn’t the smoothest V-6, but the engine’s grit is largely filtered out in the M and is more sonorous than the 3.7-liter variant in the M37. Its mechanical engine noise is well matched to that sweet VQ exhaust song that still makes pedestrians turn around and look.

The heavy hybrid componentry leaves the 4129-lb M35h weighing 270 lb more than the M37 — and 100 lb more even than the M56. The location of the mass, however, works wonders on the M’s weight distribution: the M37 carries 54% of its mass on the front axle; the M56 wears 56% up front. The hybrid, by comparison, is far better balanced at 51% front, 49% rear.

We didn’t have the opportunity to run this hybrid through a handling course (and we suspect its owners won’t, either), but in spirited driving, the M35h loses little to its nonhybrid twins. The additional weight required the use of double-piston shocks (from the sport package) and special tuning for the springs and antiroll bars. Ride quality, like other non-sport-package M sedans, is generally okay but borders on stiff — and the suspension transmits harsh impacts to the cabin far too often.

Like most other hybrids — and unlike other Ms — the M35h uses electrically assisted power steering. Infiniti’s engineers have something to be proud of here, since they’ve preserved much of the feel of other Ms in the transition. There’s not as much steering feedback as in the sport-package (active-steering) M, but there’s more than in the all-wheel-drive version — and the effort builds up just right.

The brake pedal’s feel is less successful, if only slightly. In normal driving, the pedal is acceptably easy to moderate. Quick applications result in a time lag while the system proportions between regenerative and friction brakes.

For most of the driving experience, though, the hybrid feels like a normal M. The engine starts smoothly, but admittedly not as unobtrusively as some other hybrids. Planetary gearset-type hybrid systems with two motors (like the Toyota and Ford systems) more smoothly start their engines (Infiniti’s system uses a clutch between the engine and the rest of the driveline.) On the plus side, the sandwich-type systems like the M35h’s use conventional, non-CVT transmissions and are more efficient on the highway — and they’re far less complex and expensive. The occasional small shudder on startup is well worth the tradeoff.

The M35h is very willing to keep the gas engine switched off. Infiniti says that the V-6 is off nearly half the time in normal driving, and that’s not a meritless claim. During our drive loop in a preproduction M35h, the engine was off for nearly 40% of the miles we covered — there’s a clever secondary trip odometer that keeps track of engine-off miles. The figure jumped to 57% during a 25-mile fuel-economy run, which netted an impressive, indicated 33 mpg on a mostly city-street loop. Obviously, the gasoline engine is the primary source of propulsion, so it’ll be on nearly all the time on the open road, but Infiniti says the engine can switch off during coasting at speeds up to 85 mph.

Thanks to the battery, the M35h’s trunk space decreases from 14.9 to 11.3 cu ft. With no folding rear seats and a trunk smaller than a Nissan Versa‘s, the M35h’s cargo room leaves a little to be desired. Then again, its competition is no better.

Pricing hasn’t been announced — or even finalized — yet, but you can safely expect the M35h to slot between the M37 ($47,925) and the M56 ($59,325). We’re hoping the pricing comes closer to the M37, as the M56’s pricing isn’t, in our opinion, a bargain.

Then again, the M35h’s only real competitor in the marketplace is the $58,925 Lexus GS450H. The Lexus quotes a similar total system output of 340 hp, but with EPA ratings of 22 city, 25 highway (23 combined), it gets clobbered by the new Infiniti. And its trunk is even smaller. And the Infiniti is vastly more fun to drive.

The fast, frugal, and fabulous diesel-powered BMW 335d is a full size smaller and starts at $45,025, and it can’t even match the M35h’s 29-mpg EPA combined rating. (The BMW achieves 23 city and 36 highway for 27 mpg combined.) Our experience with the 335d has resulted in highway fuel economy slightly better than the EPA rating, so on the open road, BMW’s diesel will consume less fuel. In more typical mixed driving, though, the larger Infiniti M takes the lead.

Nothing against the M56’s lusty V-8, but the M35h renders that car irrelevant for most buyers. The electric motor’s torque provides better grunt than the V-8, which is too soft in the low end of its rev range. Sure, the V-8 will probably win at the quarter-mile track, but using 35% less fuel in EPA testing, we think the M35h is the real winner. For all but the hardest-core luxury sport sedan buyers, anyway.

When we drove a prototype M35h last year, Infiniti promised that its first hybrid would provide the fuel economy of an economy car with a 1.8-liter engine. The M35h does that. What Infiniti failed to tell us, however, was that its system wouldn’t ruin the behind-the-wheel experience. And it doesn’t. That’s even more impressive than its fuel economy.

2012 Infiniti M35h

On sale: March 2011
Base price: $56,000 (est.)

L x W x H: 194.7 x 72.6 x 59.1 in
Wheelbase: 114.2 in
Track, f/r: 62.0./61.8 in

Gasoline Engine: 3.5-liter V-6
Power: 302 hp @ 6800 rpm
Torque: 258 lb-ft @ 5000 rpm

Electric Motor Power: 67 hp @ 1770 rpm
Electric Motor Torque: 199 lb-ft @ 1770 rpm
Battery Pack: 346V 1.4kWh Lithium-ion (Li-ion)
Max Battery Output: 50kW

Quoted Total System Output: 360 hp

Transmission: 7-speed automatic with sandwich-type hybrid electric drive

Tires: Michelin Primacy mxm4 245/50-VR18
Wheels: 8.0 x 18 in

Curb weight: 4129 lb
Cargo volume: 11.3 cu ft

EPA Fuel Economy: 27/32 mpg (city/highway)