schanyc

winter tire/wheel question please.

I have a set of 19" x 8.5" ET35 - VMR V710 wheels mounted with Good Year Ultra Grip WRT ice/snow tires. The tire size is 235/55-19. I used these with my Q5 fine as the size was approved via Tire Rack years ago.

I'm looking to pickup a 2013 S7 and want to see if I can use this same winter set. I know bolt pattern is the same 5 x 112 and center bore 66.6cm. However Tire Rack recommended winter tire size for the car is 255/40-19.

Can someone advise on if I need to go with the wider tire on the S7 or I can use the ones I already own? Consequences of using one over the other? I assume narrower tire better for snow but perhaps the S7 needs to sit on wider tires?

mog

in general, the S7 doesn't "need" the wider tire, i.e. the width isn't your gating factor.

i'm sure others can comment on that specific size, but with the S7 there are also issues with the rims themselves actually clearing the brake calipers.

as an example, while hartmann sells ~25-30 different styles, only like 5 of the are compatible with the S7 (while many, many more are an approved fit on the A7).

assuming they did fit, yes, they'd likely be better in the snow since they're narrower; your speedometer would be slightly off (as an example when you were going 70mph, your speedometer would only show 65): https://tiresize.com/speedometer-calibration/

snagitseven

Using one of the many tire/wheel comparison charts found on the internet, aside from any potential offset, fender or caliper clearance issues and assuming the wheel hub sizes are the same, the Q5 tire/wheel at 4.5% greater circumference will show your speedometer/odometer at 65 mph when actual speed is 68 mph.