Hello I need some help regarding changing my low profile tyre's to high profile tyre's on my 245/40/R18 can this be change to high profile. ? 

Hello Esat,

The theory about changing the tyre profile should be well documented on the websites of some of the major players in the Internet tyre suppliers. 

As I recall, perhaps (but please check and reassure yourself) changing the profile by one 'size' from say 40 to 45 should not be too drastic, but of course you are increasing the total diameter and technically this will alter the gearing. I think the theory would again point you to changing the wheels to 17 inch if you want to increase the profile to say 50. You will need to work it out yourself, but 40 refers to the tyre wall height being 40% of the tyre width, so if you wanted to change to 45 then the tyre wall height would increase by around 6mm by rough calculation. Work out  40% of your 245mm, then 45% of 245 and this will give you the difference. 

Affects on handling, gearing etc. .?? 

I would look up what wheel diameters that were available for your model and start there.

I can well understand your desire to move away from these unrealistically low profile since they were conceived to satisfy the motorists who want to constantly go around corners flat out - as we all do all of the time - don't we! The requirements of the motorists who want to drive reasonably and enjoy a smooth ride are ignored. 

Now Dunlop developed the pneumatic tyre to give comfort over the previous solid tyre..... But these low profile tyres are supposed to represent progress! 

Kind regards,

Gareth. 

Thank you for your help and the information I will look in to it.

kind regards 

Esat