new SLK AMG economy 34mpg-will petrol replace diesel soon?

[philcray]

Saw the review in the paper at the weekend - SLK AMG claiming 34mpg on the combined cycle - I appreciate that the engine runs on 4 cylinders at lower load which helps improve economy.

I also seem to recall that the 3 litre SLK does about 40mpg on the combined cycle - the question is, when are these economical engines going to appear across the rest of the range? I am considering a new model E class estate and would jump at a petrol doing a real world 40mpg (not too fussed about the performance, within reason).

I think most people would prefer a petrol engine so, with these performance engines able to record these figures, surely it is only a matter of time before diesel fall back out of favour?

[bakerstreet]

Are these road test figures or what the manufactures are claiming? Do we not take these figures with a hefty dose of salt?

The Chevvy V8 LS series engines are capable of 30mpg on a run aren't they?

The new VAG 1.4TSFI is meant to be very good for economy for a petrol.

[Stegel]

I think it will be a while yet - I've had 2 near identical C class estates as courtesy vehicles recently, both automatic, both Sport models, both with stop-start etc.. A 220CDI averaged 46mpg over varied roads. I've only had the petrol 250 for a day, but on a 100 miles of similar driving it did 30.9mpg. It has only done 1,500 miles (as opposed to 6,000 miles for the diesel) but I can't see that accounting for the massive difference.

[tcant]

I'm driving the new C350 Coupe with the 3.5 litre petrol engine. It is quoted to do 40.4 mpg on the combined cycle and after 1300 miles I have averaged 34 mpg. I think 40mpg is achievable, I just don't get much 'extra urban' driving on my route to work.

I love the free revving responsiveness of a petrol engine and paying more for diesel to get 5-10 MPG more just doesn't justify it for me.

[Cooldudeoli]

tcant said:

I'm driving the new C350 Coupe with the 3.5 litre petrol engine. It is quoted to do 40.4 mpg on the combined cycle and after 1300 miles I have averaged 34 mpg. I think 40mpg is achievable, I just don't get much 'extra urban' driving on my route to work.

I love the free revving responsiveness of a petrol engine and paying more for diesel to get 5-10 MPG more just doesn't justify it for me.

That's really impressive tbh, I hadn't realised how good the petrol engines had got.