That's right. A 2012 Infiniti M35h, after being driven 596 kilometers (370 miles), returned 36.2 miles per gallon (U.S.) – besting its official fuel economy rating by seven percent and becoming the only hybrid in the Marathon to beat its listed combined mpg figure. All of the other competing gas- and diesel-electrics, according to Infiniti, fell shy of their official combined fuel consumption figures.
The Infiniti M35h got the job done by using a lot of electric-only propulsion. Infiniti says the M35h cruised on electric-only power for 180 of the 370 miles. In other words, almost half the Marathon was covered with the M35h's 3.5-liter V6 engine not on duty. Since the M35h's engine can shut down at speeds of up to 85 miles per hour, we assume there some serious pulse-and-glide driving going on here. Still, 36.2 mpg is fairly impressive for a single motor, two-clutch hybrid. Does this imply that one motor beats two?
Infiniti wins hybrid class of UK's premier fuel economy marathon
Only hybrid taking part to beat official combined fuel consumption
Almost half the 596km course completed on electric power
The world's fastest-accelerating hybrid – according to Guinness World Records – is also in a fuel-economy class of its own, according to organizers of the UK's most prestigious economy run.
In a stark demonstration of Infiniti's new-generation hybrid technology, an Infiniti M35h driven over a demanding 596km route returned 6.49 l/100km – more than 7 per cent better than its official combined figure of 7.0 l/100km. All the other hybrids taking part, both diesel and petrol, fell short of their official combined fuel consumption figures.
In winning its class in the 2011 ALD Automotive/Shell FuelSave MPG Marathon, the Infiniti M35h showed how its innovative one motor/two clutch system enables zero-emissions running to be utilised more often, for longer periods and at higher speeds than other hybrid systems.
Overall, the Infiniti M35h cruised silently on electric power for 290 of the 596km. In other words almost half the route was completed with the 3.5-litre petrol V6 engine switched off. On one 87km leg of the economy run, the M35h ran for 48km – over 55% of the distance – on power alone from the lithium-ion batteries and electric motor, at 68PS one of the most powerful in production.
"Infiniti's Direct Response Hybrid system was developed to offer a no-compromise way of providing both performance and fuel economy and this result demonstrates how successful that approach has been," said Wayne Bruce – Communications Director.
"Achieving low fuel consumption in the official cycle tests might look impressive but helps no one if it is not readily achievable in real life.
"For a large luxury five-seat saloon capable of 0-100km/h in just 5.5 seconds to turn in more less than 6.5 l/100km in real-world driving is a remarkable result."
The Infiniti M35h can call on a total system power of 364PS from its combination of petrol V6 and electric motor. In performance the car lacks for nothing with a top speed limited to 250km/h and acceleration from 0-100km/h in 5.5 seconds. As Guinness World Records confirmed in August this year, its standing 400m time of 13.9 seconds makes it the fastest hybrid in production. Despite its high performance, the Infiniti M35h's official combined consumption of 7.0 l/100km is matched by a tax-saving 162g/km of CO2.
Economy aids fitted as standard to the pioneering hybrid include an eco setting in the Infiniti Drive Mode Selector. As well as changing throttle response and transmission mapping, for earlier gear changes, it activates Infiniti's unique Eco Pedal. Pedal pressure is gently modulated to encourage maximum engine efficiency, the pedal pushing back when the driver is needlessly heavy with the right foot. The Eco Pedal operates in conjunction with an indicator light system that clearly shows when the car is at its economical best.
"We drove as normal and the car did all the hard economy work for us," said one of the drivers, British motoring journalist Bob Murray. "The Eco Pedal and economy warning light were invaluable aids, while the dashboard graphic showing the V6/electric power delivery made it easy to make the most of the electric motor. We were often cruising along on battery power at over 100km/h."
Organised by the FleetWorld group, this was the 10th MPG Marathon. Twenty six cars took part in the two-day event which covered 596km of motorways and minor roads across some notably hilly parts of southern England.