Wednesday 17th August 2011

Diesel-Fired Merc SLK Claims 59mpg

It's no rocket ship, but it will test your bladder

---

"Thank heavens for Doctor Kegel..."

This new diesel version of M-B's SLK roadster combines almost 370lb ft of torque (and 204hp) with a claimed 59mpg average on the 'Euro-cycle'.

The company says the four-cylinder 2143cc engine puts the two-seater at the top of its class in numerous respects, although they may not be including 'pure driving joy' for afficionados of rev-happy petrol sports cars.

Still, thanks to its relatively mighty torque they claim the car accelerates from zero to 62mph in 6.7secs, and from 49.7 to 74.6mph (aka 80-120km/h) in 4.3secs, which is pretty useful flexibility from a car (they claim) can also take you from the North Sea to a Mediterranean beach non-stop. Hopefully there'll be some sort of 'porta-potty' on the options list for drivers with compromised pelvic floor muscles.

Er, is that it? Best keep it shut then.

The engine gets common-rail injection with a rail pressure of 2000 bar, as well as two-stage turbocharging and like all SLKs features a start/stop system. 7G-TRONIC PLUS automatic transmission will be standard when the car goes on sale here later this year. We're still waiting for UK prices, but the Germans are quoting €41,828.50 inc. VAT.

Externally the new version looks identical to its petrol siblings, right down to the twin exhaust system.

 

[Neil G60]

Cheap to run, quick, the roof comes off, it looks nice, it's probably built well, quite a big boot with the top up. Makes sense to me with petrol at £1.35/l

[kambites]

Seems like a fairly logical step, although it doesn't really appeal to me.

[JRich174]

Fantastic! Finally a diesel SLK!

• whips out the ol' cheque book*

[Oddball RS]

I think this kind of thing will be seen more and more, it might not be ideal but lets be honest, its better than re-engineering a C5 Audi style.

[mnkiboy]

Probably about half of the Audi TT's I see are diesel powered, so there's obviously a market for them, however wrong it seems.

Can't be long until there's a diesel powered Z4 for sale. Or is it already on sale?

[Rocksteadyeddie]

So 30mpg in the real world? The higher the official figures the less I believe them!

[Paper Lawyer]

One of the key benefits of a drop top is to hear the engine sing. With a "prestige" car like an SLK I suspect there's also an element of shouting "look at me!". Why in that context you'd want to hear a miserly diesel is beyond me....

[Caulkhead]

It's a shame they chose to use the 250 version of the 4-cyl engine as it's unrefined and clattery. The 350CDi six in current 265bhp tune would've made more sense in something with a folding roof IMHO.

[FamilyDub]

mnkiboy said:

Probably about half of the Audi TT's I see are diesel powered, so there's obviously a market for them, however wrong it seems.

Nail. Head.

[Deva Link]

Rocksteadyeddie said:

So 30mpg in the real world? The higher the official figures the less I believe them!

That'll be about right around town. Probably do 45MPG on a steady run.

[theJT]

I guess it makes sense. It's a pretty car, and I imagine a large number of the people that will buy it neither know nor care about the difference between a petrol and a diesel engine other than "Diesel is the one that gets better fuel economy right?"

[jshell]

I'm running a 2.0 l turbo diesel BMW right now and achieving 46.4mpg (520 miles from 11.2 gal tank). I sit on the motor way for most of it at around 85-90mph. Saved me a fortune and it makes the SLK figures look achieveable...

[kambites]

I'd imagine it'll do 60mpg at 70mph, or there abouts. My experience of modern cars is that you can usually achieve around the official "combined" figure on the motorway,

[roachcoach]

Who knows.

I can get 50-55ish out a rav4 real world....but then my focus 'claims' 40....perhaps in a frictionless flat universe aka: a test centre.

[kambites]

The official combined figure for the mk2 Focus ST is 30mpg, isn't it?

[roachcoach]

Yeah, but the extra urban is supposedly 40. My arse. Best I've ever seen, once, was 38 on a 20 mile run of which 19 miles was A-road at 50ish

My personal theory is the wind resistance kills it real world, the EU tests are rolling road.

[kambites]

roachcoach said:

My personal theory is the wind resistance kills it real world, the EU tests are rolling road.

Not quite true. IIRC they do a coasting stop from a certain speed to measure drag and then measure the engine output on a rolling road and combine the two sets of results to try to come up with a realistic figure.

I don't think many cars can get anywhere near their states extra-urban figures. Hence my guess that this'll do something like 60mpg on the motorway (but considerably less overall).

[J4CKO]

I dont think anyone would choose the diesel version if there were no compromises needing to be made so it makes sense, the market demands it and Mercedes make it, will be mainly company buyers but private buyers may also plump for the diesel to ensure resale in the post petrol landscape.

To be fair, on the sound front, they did the Kompressor versions or ages and they didnt sound very nice so may as well have sound economy.

[Riggers]

Is it me, or is this the first two-seat diesel 'sports car'? (and I don't use those inverted commas lightly...)

Every other soft-top or coupe diesel I can thing of is a four-seater or a 2+2.... though as I write this I have just realised that the Audi TT roadster is a two-seat jobbie... so just ignore me...

[roachcoach]

kambites said:

roachcoach said:

My personal theory is the wind resistance kills it real world, the EU tests are rolling road.

Not quite true. IIRC they do a coasting stop from a certain speed to measure drag and then measure the engine output on a rolling road and combine the two sets of results to try to come up with a realistic figure.

I don't think many cars can get anywhere near their states extra-urban figures. Hence my guess that this'll do something like 60mpg on the motorway (but considerably less overall).

Maybe. I'd read they are a by product of the emissions tests somewhere and have various other flaws compared to 'real' world driving.


I'm pretty close to book figures with the Rav4 though - just goes to show it really does vary a lot - same driver, same route, same attitude and pretty wildly out ranged. I hit the extra urban in the rav (which I should, I make the combined in the focus: it should be higher)

ETA: It may be the occasional stop that sinks the focus, pulling away wrecks the numbers so bad you may as well do a burnout whilst you're there.