175/55 R20 doesn't belong to the most popular dimensions for summer tyres - there are 3 tyre models available, which can be compared to
155/60 R15,
170/60 R17,
160/60 R14. Let's break down the sizing - 55 is height of the tyre, which is calculated as 55% of the tyre width (175mm), which means the sidewall height has 96.25 mm. The wheel diameter is R20, which means it fits to a 20 inch/508mm diameter wheel. The total circumference of the tyre is 2200.69 mm, which is very similar to 275/35 R20
(2200.69 mm), 245/55 R17
(2203.2 mm), 155/70 R19
(2197.86 mm), 225/60 R17
(2204.77 mm), 225/65 R16
(2195.66 mm), 195/75 R16
(2195.66 mm), 245/50 R18
(2206.03 mm). There are multiple speed indexes available for summer tyres in 175/55 R20: Q
(160km/h), T
(190km/h). The same goes for weight indexes: 85, 89.
