Hi wondering if anyone can help. I have a lowered st170 unsure by how much as purchased the car like this. The wheels on the car at the moment are 16" but i have been offered some 18" in a swap. Any ideas how to measure to see if the 18's would fit. Sorry not very technically minded but know a lot of you are lol

 

Try one on? Simplest way.

 

my st170 has 18s and was lowered a silly amount too, but its back on stock suspension and did not have issues at all on either as long as wheels are right offset and tyre size is correct just crack on

 

215/35s you'll need

 

Superb all ill find out the size

 

Thanks for everyones help, straight swap for the 16" wheels happy with the outcome