by Mike Tippett

Contact Mike by e-mail.

To order a Scangauge and improve your own fuel economy, visit here.

Introduction

There have been two horsepower wars in the history of the automobile: the first began in the late 1950s in the USA - ending in 1970 with the introduction of stricter emission controls; and the second began sometime very late in the “me” decade, thanks mainly to electronic engine management systems, and it continues at a fever pitch today - especially in North America!

Everyone here seems to be in a rush, and even lowly and poorly named “mini” vans like the Toyota Sienna can crack off 0-100 km/h times of 8.5 seconds, which was firmly in high end sports car territory not even thirty years ago. Today, cars that can accelerate from 0-100 km/h in ten seconds are considered “slow” by car magazines.

Vans are often the fastest-driven vehicles on many roads these days, the fast ones usually being driven by frenzied people with cell phones jammed in their ears, 30 km/h or more over the speed limit. What a statement about modern lifestyles….

Into this hectic rat race, which I hope has reached its zenith by now, the smart fortwo cdi was introduced to Canada in the fall of 2004.

The smart fortwo cdi is the definitive losing car in the horsepower war; it has a mere 40.2 net horsepower to the credit of its 799 cc, but a more impressive 100 Nm (74 lbs-ft) of torque on tap at low rpm. The official acceleration times are considered to be glacial by motoring magazines: 0-100 km/h takes about 20 seconds. That 3 seconds of this is due to the automated clutch actuation doesn’t really matter to the stopwatch. 45 years ago, that would have made the fortwo cdi the fastest sub-800 cc car in existence, about as fast as the rare Renault Dauphine Gordini 1093, with its 49 DIN horses, and 46 more cubic centimetres to play with!

With the advent of the peak oil debate in mainstream collective consciousness, it is clear to most people that the highway to hell is paved with excessive horsepower and waste, and yet the rat race continues more or less unchallenged. It is for this reason that the smart cdi, and other cars of its ilk - VW TDI, some hybrids, small hatchbacks generally - are so important. They speak to moderation instead of excess, humility instead of brashness (or worse), and offer another view of driving, and driving pleasure. It is actually possible to drive some of these cars in a very sedate manner, and derive considerable pleasure from doing just that. In fact, fuel economy geeks have sprouted up en masse and now - in some circles - it is considered to be de rigeur to have a dynamic fuel economy icon in one’s internet forum signature!

The smart fortwo in particular has been among the most influential and successful of this new wave in Canada. One reason for this, aside from its near peerless fuel economy potential (and certainly peerless at the price) is its cheeky looks, a masterpiece of modern industrial design, the icon of form following function among automobiles. Another is its availability in convertible form, and for those not so inclined, its fantastic panoramic glass roof, or large sunroof. The visibility that these features afford begs the driver (when safe) and passenger to actually LOOK at the landscape, sky, towers and birds, to enjoy the smells and feeling of the environment. The smart car is not an insular, hostile-looking cocoon like a Chrysler 300, it is a open vessel, trying to be part of the environment insofar as it is possible for any automobile to do that. Enjoying the world in cars like this does not depend upon cornering with 1.0 g of lateral force, out-accelerating the driver of the red Mustang GT to the next stoplight, or cutting off someone in traffic to raise one‘s own shattered self-esteem. I think that driving a slower car makes for a better driver.

Not all smart drivers think alike however, and there are ample engine tuning and customisation opportunities for the fortwo cdi, though even the best of the remaps still keep the car at the bottom of the performance tables. But there is something noble about being an underdog……………..

Fuel Economy

Transport Canada rates the fuel consumption of the smart fortwo cdi at 3.7 (manual mode) to 3.8 (softouch automatic mode) litres per 100 kilometres on the highway, and 4.6 L/100 km in the city, for an average of 4.2. For the “Imperalists“, that is 76.3/74.4 MPG highway, 61.4 MPG in the city, for an overall average of 67.3 MPG.

Interestingly, due to the inferior quality of Canadian diesel fuel - it is lower in cetane than the European equivalent, and will have far higher sulphur levels until later in 2006 - the engine fuelling parameters had to be adjusted by smart on the Canadian model, to the detriment of fuel economy. In Europe, the CE highway fuel consumption rating is a low 3.1 L/100 km (over 90 MPG).

While several Canadian cdi drivers manage to keep their average fuel consumption at or near the Transport Canada highway estimate (say under 4 L/100 km), most are reasonably content if they are averaging 4.5 L/100 km or less. Of course, these numbers depend upon the prevailing driving conditions of each vehicle, and the driver’s technique. Still, these numbers are nearly impossible to achieve as an average in any other car that is presently for sale in Canada.

Some smart owners have successfully probed the limits of the smart fortwo cdi’s fuel efficiency: Keith Hebert of British Columbia has conducted two towering economy runs of special note, one in which his car returned 113 mpg (imperial) (2.49 L/100 km) and another where he eked out slightly better than 100 mpg (US) (under 2.3 L/100 km)!! It is generally accepted that the most efficient speed for optimal highway fuel economy is 80-85 km/h, at which speed the car’s powerplant is turning over at a mere 1850 rpm, just into the peak torque band, and the car‘s less than optimal drag coefficient of 0.38 and its considerable frontal area are not yet fighting the wind too hard. At that speed, fuel consumption is around 2.9 or 3.0 L/100 km in normal conditions. But in many cases, driving that slowly is not possible on a sustained basis, so suffice it to say that keeping highway speeds to 100 km/h will reward the cdi driver with fuel consumption in the 3.3 - 3.7 L/100 km range.

My own fortwo, a cabriolet model, has a lifetime fuel economy average of 3.82 L/100 km over 43,000 km, or 74 MPG. That is the result of somewhat careful driving, usually at the local speed limit, but often with the top down (bad for drag) with the heated seats on full blast, or with the top up and air conditioning on full blast, and the occasional speed run and blast of acceleration (!) from a stop.

blogmaster’s comments:

We should also draw attention to the story about Craig Brooks from Welland, ON who is saving $7000 a year in fuels costs by driving a smart!!

Performance

I have already written about the fortwo cdi’s slow acceleration in the introduction. But it is not as bad as the numbers would appear to show.

As mentioned above, it is the smart’s convenient - but pedestrian - automated sequential manual transmission that is partly to blame. The clutch is actuated electronically, and sensibly, the software engineers have programmed a modicum of self-preservation into the shifting and clutch actuation protocols.

When magazines test cars, they abuse them horrifically, revving the engines to redline and dumping the clutch off the line, and power-shifting a manual gearbox (leaving one’s foot buried in the accelerator during the gear change) to achieve the best times. This kind of behaviour would not be tolerated by any car for long, and thankfully it is not possible in a smart fortwo, because the car knows better! Three gear changes are needed to hit 100 km/h in a fortwo cdi, whereas many modern cars need only one. And the smart’s gear change is slow compared to a power shift, or the shift of a high performance sequential manual gearbox like Audi’s DSC or BMW’s SMG II. Scrub about three seconds from the fortwo’s acceleration time to 100, from the perspective of the “butt dynamometer” (how fast the car “feels” when in gear).

When the cdi is in gear, the pulling power is strong, thanks to the ample torque, though the peak torque band is on the narrow side (1800 to 2800 rpm). Fifth gear in particular is sufficient in a standard car to haul two large people and their luggage up an 8% gradient at the local speed limit (provided it is under 100 km/h!). The top speed of the fortwo is limited to 135 km/h, but in Canada that is more than enough to get into trouble from the constabulary.

Is the fortwo cdi too slow to drive safely in Canada? No! You can’t drive it as though it is a Subaru WRX Sti when merging with traffic, but if driven defensively, and sensibly it is 100% safe.

Modifications

There are a whole range of modifications that people do to their fortwo. Following are a few examples:

Appearance:

• Body kits by Brabus, Michalak, Lorinser and others
• LED side marker lights
• LED bulbs everywhere!
• Raised chrome “smart”, “cdi” and “fortwo” lettering
• Speciality vinyl “wraps”
• Special paint schemes for body panels
• Special trim pieces

Appearance/function:

• Wider wheels and tires by smart (coreline, strikeline, spikeline), Brabus, and many aftermarket brands
• Sports suspensions by Brabus, Eibach and others
• OEM fog lights for the front grille (putting the turn signals back into the headlamp units)
• Custom taillight units, or return to European model taillights
• Aftermarket exhaust systems like Blindschleiche
• Brabus front spoiler
• Window/lens tinting
• Sound systems
• Onboard computers, like the Scangauge

Function:

• Cruise control, looks/works like the OEM system available in Europe
• Convenience switches for passenger side window, raising windows with power off, MP3 interface, etc
• Trailer/towing packages

Engine modifications:

• Remaps by various manufacturers and specialists, to increase power (up to 65 HP) and torque (up to 140 Nm, and beyond!)
• Speed limiter removal (part of some higher powered remaps)
• Oil pans with drain plugs
• Oil coolers (recommended for high output engines)
• Spin-on oil filter adaptors

That is just a brief taste of the various modifications that are common among smart car owners!

Conclusion

The smart fortwo cdi is not for everyone, but it is a unique and satisfactory performer on the road, with stellar fuel economy and massive potential for customisation. Driving one makes for safer, more defensive progress in modern traffic. Parking in cities is a snap and small gaps that other cars won’t fit through are child’s play for the smart. It is the perfect car for a changing world, a statement: less is more.