I would have thought it would have gone the other way, the smaller wheel would have to spin faster, albeit the tyre walls are taller. Maybe one cancelled out the other.So i changed my whel size from 18" merc rims to 16" - did a manifold clean, time ng chain tensioner and tyre size went down from 245/40/18 to 205/55/16
After these jobs i went on my first long drive,i could believe my eyes. 61.4mpg on my first 230 mile trip to scotland and then 62.8mpg on my return today. Its goven me 630miles and my fuel light hasnt come on yet. This was steady 70mph with slow acceleration, using momentum of the car to hold the speed. On the same trip previously ive been about 10 times, i couldn't get over 50mpg on screen no matter how hard i tried.
I am over the moon but very surprised as to why its suddenly gone up.
Is it the reduction in tyre and wheel size thats improved the mpg!?
Its given me 630miles from 50litres which is a real 57mpg!!!! I tried this from rim to rim so i know it's accurate .
The very reason I can’t get anywhere near the mpg figures of the S210 E320cdi (50mpg on a good run) which was on 215mm wide tyres all round compared to the S212 E350cdi (best I’ve seen is 42mpg) on 245mm front and 265mm rear tyres - retrograde progress on emissions unfortunately but the tyre manufacturers must love the profit from the lower section tyresWider tyres equals more rolling resistance and lower fuel economy.
Have a look at any manufactures data sheets and you’ll see higher emissions figures for the same car with bigger wheels and wider tyres. It’s why so many come with narrow tyres now to reduce the emissions figures.
So i changed my whel size from 18" merc rims to 16" - did a manifold clean, time ng chain tensioner and tyre size went down from 245/40/18 to 205/55/16
After these jobs i went on my first long drive,i could believe my eyes. 61.4mpg on my first 230 mile trip to scotland and then 62.8mpg on my return today. Its goven me 630miles and my fuel light hasnt come on yet. This was steady 70mph with slow acceleration, using momentum of the car to hold the speed. On the same trip previously ive been about 10 times, i couldn't get over 50mpg on screen no matter how hard i tried.
I am over the moon but very surprised as to why its suddenly gone up.
Is it the reduction in tyre and wheel size thats improved the mpg!?
Its given me 630miles from 50litres which is a real 57mpg!!!! I tried this from rim to rim so i know it's accurate .