1
Golf mk7 / Re: Tyre Sizes on TCR
« Last post by SRGTD on Today at 05:47 »@pixelcellar - Below are the results from the calculator on www.willtheyfit.com of fitting the wheel/tyre combination you’re proposing to fit compared to your existing wheel / tyre setup;

You’ll see that fitting tyres with a higher sidewall height increases the radius and circumference of your car’s wheel / tyre combination which will result in a speedometer error; with your proposed setup the speedo will under-read by 3.6% so the indicated speed displayed will be less than the true speed being travelled. I’m assuming you’re in the UK - be aware that from a legal perspective in the UK, while it is permissible for a car’s speedo to over-read by up to a pre-defined margin, it must not under-read by any amount (presumably to stop drivers unknowingly exceeding the speed limit) - see article at the link below;
https://www.thecarexpert.co.uk/how-accurate-is-a-car-speedometer/

You’ll see that fitting tyres with a higher sidewall height increases the radius and circumference of your car’s wheel / tyre combination which will result in a speedometer error; with your proposed setup the speedo will under-read by 3.6% so the indicated speed displayed will be less than the true speed being travelled. I’m assuming you’re in the UK - be aware that from a legal perspective in the UK, while it is permissible for a car’s speedo to over-read by up to a pre-defined margin, it must not under-read by any amount (presumably to stop drivers unknowingly exceeding the speed limit) - see article at the link below;
https://www.thecarexpert.co.uk/how-accurate-is-a-car-speedometer/
Recent Posts



