Correct offset for 20" wheels
 

I am considering a set of winter wheels and tyres for my D3 S8. What is the correct offset assuming that I stick with 20" wheels. Is it possible to go down to 19" wheels (I think more tyre and less wheel better for winter rubber)? If so, does the offset change.

Maybe of interest, sorry I don't have the offset to hand but ET43 springs to mind.....

http://forum.a8parts.co.uk/showthread.php?t=13701

Thanks Paul. I could be very interested if only I can confirm that 19" wheels will fit the S8. By the way, the details in the ad actually says that they are ET44.

Mine were et43, I suspect et44 was also an OEM option as 1mm is very close +++ Looking at the epc “google Audi parts catalogue” et40-45 seems correct.

I also suspect 19s will be fine, check the tyre pressure sticker as a quic reference or check epc to be sure. +++

The spare wheel on my S8 is a 19in, so I'm confident it will fit. :)

Thanks `paul. Sorry to be dumb but what is epc?

Electronic parts catalogue +++ Not sure if posting links is allowed, but google "Audi Parts Catalogue EPC" and you should find a few +++

I think you'll find quite a range of offsets "fit" a D3, from ET44 or higher through to about ET25.
The question is what will fit over your S8 brakes. I would estimate that the lower the offset, the better the brake clearance, though this also depends on wheel design.
You should be fine with an OEM type 19" wheel.

The only other issue with offset is what is the optimum for handling, as Audi will design the suspension for a specific track to provide for a particular steering geometry.
There will be a degree of tolerance in this, but the further away from the optimum track you get by either increasing or decreasing offset of the wheels (and thereby altering the wheels virtual centre), the more you decrease the optimum handling of the car.
It's all %'s of course.

Thanks all, very helpful.
Happy New Year!

Here's a PDF extract from the July 2014 Audi Wheel and Tyre Guide.

S8 on Page 2 ...

Julian