I've been reading for ages on equivelent tyre sizes, but no-one ever seems to mention the width of the rim in all this. Surely any given tyre diameter will change, the narrower the rim it is squeezed on to... and there must be a guide to safe, or optimum, tyres for a given road wheel size.. Has anyone ever seen a table listing suitable tyres sizes to choose from?
My problem is this: I have 175/70 13 on a 5.5J rim on a spitfire and they rub on the wheel arch lip. So i need to go narrower and/or lower profile. Any suggestions anyone - my un-skilled opinion says I should go narrower, as the rear will be left on 175/70's and narrower means the front wont look noticably smaller.