Bridgestone Turanza T001 is a summer tyre made in total of 69 sizes, ranging from R15 to R15 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 225/45 R18 is 40mm wider than the narrowest dimension (185) and 0mm narrower than the widest one (225). This tyre profile of 45 means the sidewall height of the tyre is 45% of the tyre width (225mm), which results in 101.25mm sidewall height. In 225/45 R18, there is only one possible speed index for Bridgestone Turanza T001 - "V", which is good for speeds up to 240 km/h. In 225/45 R18, Turanza T001 usually competes against Efficient Grip Performance, which is a tyre from Goodyear with a rating of 84%, compared to 37% of the Bridgestone in question.