Matt76
Member
I was thinking (don't like to make a habit of it) about the speedo inaccuracy in our cars, and saw a post in the tyre section how someones fuel economy got worse when putting bigger tyres on.
Lets do an experiment....
If our speedo from standard was say 10% out, maybe a bit extreme but lets stick to nice round figures. If we are getting 10L/100kms by the odometer, we are really only doing 90kms so the fuel economy should be 10l/90kms or 11.1L/100kms. If we changed to a bigger tyre and corrected the speedo innacurracy, anything under 11.1L/100kms by the odometer is actually a gain in fuel economy? So if your fuel economy went up by 2L/100km when you put bigger tyres on, it has really gone up bugger all.
Am I correct or full of shit as usual?
Lets do an experiment....
If our speedo from standard was say 10% out, maybe a bit extreme but lets stick to nice round figures. If we are getting 10L/100kms by the odometer, we are really only doing 90kms so the fuel economy should be 10l/90kms or 11.1L/100kms. If we changed to a bigger tyre and corrected the speedo innacurracy, anything under 11.1L/100kms by the odometer is actually a gain in fuel economy? So if your fuel economy went up by 2L/100km when you put bigger tyres on, it has really gone up bugger all.
Am I correct or full of shit as usual?