oldman

I've got a question about tire/wheel size and gear ratio if someone could help.. 331 gears with 275/60 17's on the back, Wont this tire/ wheel size actually change the ratio?
If this is a stupid question please forgive my iggnorance. I'm new at this.

Poco

If your car came with the stock tire size then (about 27" overall diameter) then you stick a tire thats about 28"(overall diameter)tall then you made your gears a little taller like a 3;15,not sure exactly about the ratio but it does change and it could throw your speedo off a bit.