OIL-BURNING ISSUE

Motoring News - Friday December 14, 2007

DIESEL EXECUTIVE SALOONS

OIL-BURNING ISSUE

Feeling the pinch of fuel prices but can't downgrade the car? Try diesel

WIWAT CHANG

Why are they here?

These two luxo executive saloons are the oil-burning variants of the Mercedes-Benz's and BMW's core-selling models. The other brand offering a diesel in this segment in locally assembled form is Volvo with its S80 D5 - but it isn't available yet for press review.

The E220 CDI was Thailand's first officially available diesel luxury saloon some six years ago, but this sample comes in its latest facelift guise and with a newly revised engine producing 20hp more at 400rpm lower and 60Nm more torque.

The unpopular E270 CDI - due to a far higher price because of more excise tax - is no longer on sale making the current E220 the sole diesel contender.

Mercedes-Benz Thailand now does away with the entry-level Classic trim - so popular with five-star hotel and airport limousine fleets - and offer only the top-end Avantgarde trim to better keep its posh status in the hi-so market.

The 520d is Bee-em's first crack at the diesel lux market last year and has recently been given the mildest of an update a few months ago. The 163hp oil-burning unit is unchanged for now.

We waited more than a year to get both of these cars for a shootout and when the revised Benz was made available, we wasted no time.

We were impressed with the Bee-em last year, so let's see if the Benz can top it perhaps with the improved engine.

What do our hearts say?

Honestly, we could never expect a Benz to out-handle a Bee-em and that's how we expected them to drive. But the new Benz diesel unit is somewhat of an unknown quantity.

On paper, the performance could be neck and neck with almost identical horsepower to weight ratio. However, if torque to weight ratios were calculated and has anything to do with on the road performance, the Benz wins with 248Nm/tonne versus the Bee-em's 217.

From standstill to 100kph, the two are virtually just as fast but with Bee-em seemingly having less turbo lag.

In real life, the E220 has pretty good pick-up anywhere from 2,000rpm onwards and at highway speeds seems an effortless cruiser. It's only when you bring the 520d into perspective that the differences become clear.

While the Benz needed a deep breath (turbo lag) before churning out all the torque, the Bee-em has dismissed the silver star by several cars' length. It might be due the relatively sluggish response of the Merc's gearbox or just the lag - or both. At least, the Benz unit is more refined at slow speeds.

Downtown, the Bee-em still has an edge over the Benz with a more responsive drivetrain that lessens the nag of bumper to bumper traffic.

And the handling? The Merc would get A for that, while the Bee-em deserves AA. Nothing in this car class in this country is more agile than the 5 and with progressive and feelsome brakes to match.

The two Bee-em's downsides are the complicated i-Drive control for audio and the rather harsh ride over bumps thanks to the run-flat tyres. But the E220's audio system is not all good news for it cannot play an MP3 CD like the 520d can.

What do our heads tell? You care about your image but more worried about fuel expenses, that's why you're checking out these two diesels.

So, the bottom line is that the Bee-em is about 1kpl more frugal than the Benz on the average at 14.4 and 13.4 respectively. A close call.

Then its down to simple arithmetic. The Benz costs B4.05m and the Bee-em nearly half a million cheaper at B3.6m. Over the next five years or 100,000km, you'd also need to fork out high five-digit figures for scheduled maintenance while that expense is already included in the Bee-em's retail price.

Despite The Redbook's lower forecasted resale value for the Bee-em, the 520d is still a better value package overall.

What do we really care for?

Even if your parents' last will state that you must not own any brand of cars other than Mercedes-Benz, we'd still urge you to test drive the Merc first and then Bee-em.

We're certain you'd hate your parents for not letting you buy the better driving car which, in our opinion, is the one you're not allowed to own.

Simple, for the zillionth time, the Bee-em beats the Benz not just with superior driving dynamics but with better value. Maybe you can have your children buy one for you.

Bangkok Post