Aug 21, 2012
Will they fit my A3?
Are they 5 x 100?
What's the offset?
And those tyres are slightly too big, you could use them, but your speedo wouldn't be very accurate. You need 225/40
why would the speedo be out if a tyre was wider ? confused lol
Because the rolling circumference has increased by 25.2mm pushing the speedo out by -1.24%...not much out, but still out.
if the tyre is wider ? i thought the wheel size and profile of the tyre determened the circumferance ?
so a 355/40/18 has a larger cirumference than a 205/40/18 ???
Online Wheel & Tyre Fitment calculator. Offset, Tyre stretch and Rolling Radius calculator
the profile number is a % of the width.
So a 225 / 40 means the height of the tyre is 40% of 225.
A 335 / 40 is 40% of 335.
Therefore, you make it wider, it gets taller too.
If you look at the tyres fitted to the RS4 for instance, they used 255/35r18's, which are pretty much identical in circumference to the 225/40r18's everyone uses on the S4.
The profile, in this case 40, is a percentage of the width. Its not a size, not 40mm.
They are pcd 100 and 112. Will they cause issues will rubbing on the wheel arch?
oh - nice to know this !!!!
depends on width and offset.
But at a guess they will be the same as mine, 18 x 8, offset of 45, meaning you will need spacers to clear thew struts, but no arch rubbing no. For the record I run 15 and 20mm spacers.
replicas are generally the correct offset @ET35, but later ones are ET45. With 235 tyres, I would say they will scrub on your arches on an A3, an S3 would be ok, as they have a bit more room to play with being wider etc.
Can I jump in here as well? Trying to see if 9jx18 wheels with 35 offset would fit? Would need 20mm adapters as well so would the offset go to 15 or 55?!
offset would go to 15 with 20mm spacers.
Wheel Offset Calculator
measure your current clearance and then put the wheel specs in
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