A Speedy Diesel
Frank S. Washington, Fri, 07 Aug 2009 03:08:42 PDT
DETROIT - The 2007 Mercedes- Benz E320 BLUETEC is a bit of brute wrapped in a subtle sedan's sheet medal. We spent a short week test driving the car and we were mightily impressed.
First let's deal with BLUETEC. In a phrase, it reduces nitrous oxide emissions from diesel engines. For those of you who care, BLUETEC comes in two versions. In the E- Class an oxidation- type catalytic converter and particulate filter are combined with an improved, extremely durable NOx trap system and an additional SCR catalytic converter.
The second BLUETEC version is even more efficient. Here, AdBlue, a non- toxic aqueous solution, is injected into the exhaust- gas stream, causing ammonia to be released. In the downstream SCR catalytic converter the ammonia then converts up to 80 percent of the nitrogen oxides into the harmless natural products of nitrogen and water.
In principle, Mercedes- Benz says BLUETEC is capable of meeting the world's most stringent exhaust emission standards. All of this comes straight from Mercedes- Benz's press materials. We'll leave it to government testing agencies to insure that the system can do what Mercedes says it can do in terms of emissions. It probably can, or BLUETEC wouldn't have gotten this far.
So in today's new world, when you see a Benz with BLUETEC on its butt, it is diesel powered. And power is the forgotten word when it comes to diesels.
Today's diesels tend to double their horsepower rating in torque and all of that torque usually kicks in at a low RPM. What that means is that diesels supply a bunch of power to the pavement at low speeds. And when a diesel is not hauling or towing something, that power translates into awesome, push you back into the seat, acceleration from just about any speed.
Look at the E320 BLUETEC. It has a V6 turbocharged diesel engine that makes 208 horsepower. Seems mundane enough., however, this engine produces 388 pounds- feet of torque and its all there from 1,600 to 2,400 RPM.
For us, that translated into acceleration on the expressways here that was scary. We had to drive the E320 BLUETEC with the respect we give vehicles with twice as much horsepower. On expressways, we easily approached 90 mph and really didn't know it. Just a touch on the gas pedal sent us past 80 mph.
However, most of our time was spent on surface streets darting form here to there because of detours caused by the shut down of our main high speed artery, the Lodge Freeway. That's what makes the E320 BLUETEC's performance even more impressive. We used a little more than a quarter of a tank of fuel and racked up 210 miles.
Indeed, the E320 BLUETEC had an EPA rating of 26 miles per gallon in the city and an amazing 37 mpg on the hwy. The combination gave the E320 BLUETEC a range of 700 miles.
There was much to say about our test car. It's seven speed transmissions was as smooth shifting as any gear box we've come across. Our BLUETEC was so quiet that we couldn't even hear the engine when we were in the car. And there was virtually no soot or smoke that we could see coming from our E320 BLUETEC's exhaust.
Our car was equipped with a couple of options that pushed the price to $57,835. It had an electronic trunk closer, a navigation system, satellite radio, heated front seats, rear- window shade, a hands- free communication system, keyless go, adaptive Bi Xenon headlights with curve illumination and headlight washers.
Quite frankly, we thought the sticker contained a premium because of the diesel technology. But when we checked www.mbusa.com we found that E320 BLUETEC, with a base price of $52,325 is only $1,000 more than a gasoline powered E350.
With the price of a gallon of gasoline now more than $3.00 - again - - a car that can get us from here to Chicago and back with fuel to spare is definitely worth a look at any price.