should be obvious: you travel less miles on speedometer but use similar fuel = less mpg on the computer, not in real life.

When I fitted 275/45 x 20's I found the speedo reading to be more accurate as well, as for mpg the trip computer is so inaccurate anyway I totally ignored it. 275/40 x 20" and 255/50 x 19" were the only factory size/option fitted to the facelift RRS1, the preface-lift did have 17" and 18" option I believe for certain markets, the different tyre/wheel sizes although different the overall diameter/radius will be approximately the same, so imagine there is no need to have to have a selectable different speedo setting for every wheel size.

Cheers
Col

Last edited by Col on Mon Aug 05 2019 11:52pm. Edited 1 time in total

Yes you should really do your own calculation from refill to refill, saying that mine is not far far off. on 275/40/20 atm.

If anybody runs a S/C and worried about fuel I think they have the wrong car

Cheers
Col

I'm not, ru? at the moment it's saying 3.4 km to the liter - know it can do better but hey it's summer with beaches etc.
Wouldn't touch a derv with a barge pole. had one in my life, 1 too many.

Thanks for pointing out it was obvious Rover, it’s what I figured and I’m not worried about the cost per mile just the change and wanted the confirmation. Thanks again

Drive on -