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DaimlerChrysler Introduces the New smart fortwo cdi: 71mpg US, 88 gCO2/km

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The new smart fortwo cdi.

DaimlerChrysler has introduced the new version of the smart fortwo cdi: a diesel city car that offers fuel consumption of just 3.3 liters/100km (71 mpg US) with carbon dioxide emissions of 88 g/km.

The new smart fortwo cdi features an enhanced 799cc engine that develops 33 kW (45 bhp) of power with torque of 110 Nm (81 lb ft). That represents a decrease in fuel consumption from the prior model of around 13% with an increase in both power and torque of 10%.

The engine uses a new common-rail direct injection system which builds up high injection pressure of up to 1,600 bar (previously: 1,350 bar) even at low revs, and injects the fuel into the combustion chambers with newly developed six-hole injectors, enabling an even more efficient combustion process.

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The new fortwo cdi engine. Click to enlarge.

The three-cylinder engine has also adopted two-phase fuel injection from the CDI engines of its sister brand Mercedes-Benz. A few milliseconds before the main injection a small quantity of diesel is injected into the combustion chambers where it ignites and preheats the cylinders. This results in a noticeably quieter combustion noise level than an engine without this pilot injection. The engine control unit calculates how much fuel is needed and the interval at which pilot injection and main injection take place.

A compact turbocharger is housed in the exhaust manifold. The compressor wheel has a diameter of just 31 millimeters, yet it rotates at up to 290,000 rpm and builds up maximum charge pressure of approximately 1,150 millibars. This charge boost enables the engine to provide 85 Nm—more than three-quarters of the maximum torque—at 1,500 rpm. The smart fortwo cdi accelerates from 0-100 km/h in 19.8 seconds and reaches a top speed of 135 km/h (84 mpg).

As with the earlier models, the engine of the smart fortwo is fitted transversally in space-saving mode in front of the rear axle and inclined at an angle of 45 degrees towards the rear. The consistent use of lightweight materials means that the diesel engine weighs in at just 86 kilograms. The crankcase features a state-of-the-art diecast aluminium bedplate design and the cylinder head and cylinder head cover are likewise made of aluminium.

The three-cylinder diesel engine controls emissions in two stages. The high-tech common-rail injection and the efficient combustion process deliver a low level of engine-out emissions.  Depending on the driving situation and the engine load, up to 60% of the previously cooled exhaust gas is returned to the combustion chambers where it is combusted once again thus greatly reducing nitrogen oxide emissions. The exhaust gas recirculation works with an electropneumatic actuator which enables it to react quickly to changes. An oxidation catalytic converter and an open diesel particle filter are responsible for the aftertreatment of the exhaust gases. These are housed together with the exhaust silencer in a stainless steel case. The smart fortwo cdi is Euro-4 compliant.

The three-cylinder diesel engine works with a newly developed automated manual five-speed transmission which the driver operates by briefly tapping the shift lever on the center console. When briefly pushed forwards the transmission shifts to the next highest gear. Gently pulling the shift lever backwards is sufficient to shift down. Shift paddles on the steering wheel are optionally available and come as standard in the pulse model line. An automatic transmission mode is also available for all equipment variants.

The clutch is opened and closed by an electric motor—there is no clutch pedal in the new smart fortwo cdi. To enable quick intermediate spurts the smart engineers have developed a kick-down function that is activated with the accelerator pedal. This enables the driver to spontaneously change down by one or two gears and to make even better use of the engine’s low-speed torque.

The new smart fortwo cdi also features an extensive range of safety equipment making it, according to DaimlerChrysler, one of the safest cars in its class. The fortwo offers an anti-lock braking system (ABS) with electronic brake-force distribution, electronic stability programme (ESP), brake assist, full-size airbags for driver and passenger, seat belts with belt tensioners and belt-force limiters, safety seats with integral seat belts and the tridion safety cell.

The new smart fortwo cdi is available as a coupé and a cabrio.

Comments

Jacques R.

I was in Germany last September. I rented a Smart car for a day. I really enjoyed driving it. The shifting was different and enjoyable. I'm looking forward to buy one, I live in NM.

Andrew

My wife and I stood in line for 2 hours to test drive a SMART through the streets of Baltimore during the SMART car tour last August (2007). As background, I'm not a small guy - I work out heavily, and at the time I weighed about 238 at 6' tall. For an idea of how I'm built, think Terrell Owens (NFL). 18" neck, wear a 52L jacket, 34" waist.

My experience with small cars (including our current Mercedes SLK) has been that they're okay for short rides, but anything longer than 45 minutes become very uncomfortable - both in terms of shoulder room and leg room - and in the case of the SLK, headroom as well. Performance with these cars ranged from non-existant (mitsubishi EXPO LRV) to phenomenal (SLK) and everywhere in between.

While waiting in line, before the test drive, SMART USA repeatedly played a video that showed the crash test of a SMART into a wall, head-on into a Mercedes E class, and one where they rammed the SMART in the side. In no instance was the integrity of the passenger compartment violated. Let's see another 12k vehicle handle a head-on crash with an E-Class!

After a couple of hours, and long conversations with the others in line, I reached the test-drive representative. Instead of my wife and I riding in the same car, we each got to drive a car, and were accompanied by a SMART car rep to explain the features of the vehicle. I sent my wife with the ponytailed guy while I rode with the cute woman.

The SMART, surprisingly, had an abundance of shoulder and leg room. In fact, I had to slide the seat FORWARD to comfortably reach the pedals. In terms of legroom, it reminded me of my Honda CRX Si from the early 1990's (another 2 seater). Headroom was more than ample - even though we have the cabriolet reserved, I test drove the passion (mid-level). I had a couple of inches above my head, plenty of space for my legs, and my left shoulder did not rub against the door. It had the “driver’s seat” space of my old Ford Taurus SHO.

My wife, test driving another passion, liked the visibility while in the car. She's not that tall, only 5' 5" or so, and she said she felt like she was driving her old Jeep Grand Cherokee because the seats sit so high.

The performance wasn’t exhilarating, but it WAS adequate. Given that I'll be driving this car on the streets of Baltimore City, and not racing on the autobahn or driving interstate on I-95, I don't need 0-60 times below 8 seconds and top speeds electronically limited to 155 mph. What I need is a car that can fit into tight city spaces, especially in what's left of a spot after someone in a Ford EXCURSION or GM 1500 / 2500/3500 has taken up more than one space, and a vehicle that gets good mpg in stop & go situations.

I'll buy the first generation US SMART with the gas engine - even at 12k. Previous posters commented on the price being very high compared to chevettes and Datsun B210's, but look what you receive - start-of-the-art safety features, including electronic stability control, ABS, front and side curtain airbags, the safety cell, etc.

Fuel economy, although not 60-70 mpg, is pretty impressive - for those of you who doubt it, take a sampling of the next 5 people who walk past you and ask each of them about their average mpg figure for the vehicle they are currently driving. 45 mpg is 50% higher than what I currently get with my Ford Focus, and that is even after the EPA messed up the efficiency with all the additional emissions requirements. When the diesels come out, I'll sell my little gas powered SMART for a diesel powered SMART, and put a Greasel kit into it to run WVO. It'll be faster (more torque) and more efficient.

So, as a future SMART owner who has sat in, touched, felt, and driven the SMART Fortwo passion, I ask the rest of you who comment to please base your comments on fact – not conjecture; and experience – not “belief”. Thanks! Have a SMART day!

David

Yes, they do have a cup holder. 2 as a mater of fact. My wife and I drove the Smart a couple of days ago and we enjoyed it. We thought is was a lot of fun. I would like to see the diesel here in the USA soon. We are going for it and plan on putting up the $99 as soon as we can get back to the dealership. Some people are buying them to sell on e-bay at a huge profit.

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