Winter tires Question

[mlc2000]

My car has 15" summer tires and 14" winter tires.
There is a settting on my dash computer to change the speedomter based on winter tires... + 10mph or - 10mph.

Which setting should i choose for my winter tires ?

[cwb27]

What's the tire size of the summers (OEM) and winters?? It will be on the tire side wall in the format of 123/45 R(rimsize).

10 mph (16 km) is a HUGE amount, most snow tires only throwoff the spedo by 2-5%. Assuming of course you're not using an exact OEM diameter replacement.

[mlc2000]

What's the tire size of the summers (OEM) and winters?? It will be on the tire side wall in the format of 123/45 R(rimsize).

10 mph (16 km) is a HUGE amount, most snow tires only throwoff the spedo by 2-5%. Assuming of course you're not using an exact OEM diameter replacement.

I will check the setting numbers again. Its been a while since I looked

[ES_Revenge]

Yeah that's a huge difference. What kind of car is this? I don't think I've heard of anything like that before... Report back on the tyre sizes and we'll see how the overall diameter compares betweent the two.

[torlou]

http://www.miata.net/garage/tirecalc.html

You should stay within 1% or so.