tazman007
15-08-2013, 09:31 AM
I'm looking to buy a set of aftermarket wheels to put winter tyres on come the winter. Currently I have the 20 inch rims, but looking to downsize for the winter.
I'm looking to go the 17 inch route as this is (apparently) possible, the ideal specs of the wheel for the A7 would be 17X8j with an offset of 30 (with a play of 5mm so could get a wheel with an offset of 35), tyre specs would be 235/55 r17. I've read that going with thinner tyres would help with traction in the snow/ice hence the 17 inch route.
Interestingly, if you put the above figures in the following site to work out the rolling radius: (hope this is OK to post this link??)
Online Wheel & Tyre Fitment calculator. Offset, Tyre stretch and Rolling Radius calculator (http://www.willtheyfit.com/)
Changing from the 20 inch to the 17 inch will only result in 0.46% error in the speedo. Do the same for the 18 inch (ideal specs - 18x8.5J, offset 32, tyre specs of 255/45 r18), this will result in a speedo error of 1%.
So, anyone gone down the 17 inch route with the A7 as I'm pondering between the 17 or 18 inch.
Thoughts/comments welcome :)
I'm looking to go the 17 inch route as this is (apparently) possible, the ideal specs of the wheel for the A7 would be 17X8j with an offset of 30 (with a play of 5mm so could get a wheel with an offset of 35), tyre specs would be 235/55 r17. I've read that going with thinner tyres would help with traction in the snow/ice hence the 17 inch route.
Interestingly, if you put the above figures in the following site to work out the rolling radius: (hope this is OK to post this link??)
Online Wheel & Tyre Fitment calculator. Offset, Tyre stretch and Rolling Radius calculator (http://www.willtheyfit.com/)
Changing from the 20 inch to the 17 inch will only result in 0.46% error in the speedo. Do the same for the 18 inch (ideal specs - 18x8.5J, offset 32, tyre specs of 255/45 r18), this will result in a speedo error of 1%.
So, anyone gone down the 17 inch route with the A7 as I'm pondering between the 17 or 18 inch.
Thoughts/comments welcome :)