Q. Can I upgrade my tyre size from 175 70 r14 to 185 60 r15 on same rim?

Manufacturers do leave room in the wheel well for a calculated upsizing of tyres and wheels on their cars. This is done so that owners can upsize the tyre and wheel size to increase performance and or increase traction on different road conditions. The ideal maximum calculated upgrade that can be done without upsetting the cars driving dynamics is around 3% plus or minus of the diameter of the original tyre. You may have 15-inch wheels installed in your Volkswagen Polo. You may check out the following articles for more details regarding the same:- Modifications and Upsizing Tyres - Upsizing Tyres

Yes you can up size tyres Better breaking force