Tyre size info

**JustinM3** · 05-02-2007,02:07 PM

Hello, am new, and not an Audi owner, although do own a quality German vehicle

Just been lumbered with a set of 215/55R16 tyres.
Neighbour has an Audi A4 estate circa V plate I think (private plate) fitted with 205/55R16 tyres.
Anyone use the 215's, or know if they'll fit? Clearance looks fine on rear, front maybe too close to strut - reason I've got myself lumbered with these tyres

Also, a mate has a P plate Audi A4 1.8 turbo (150 bhp model).
Anyone tell me the size of tyres these use? He can't, he lacks sense...

Many thanks, Justin

**devonutopia** · 05-02-2007,02:47 PM

The difference will be marginal between 205 and 215.

Essentially the 205/55 means a 205mm wide track, and the profile is 55% (i.e around 115mm?) Going to 215mm means this profile will just go up by about 5%, i.e around 5mm, and 10mm overall bigger diameter, which means a 31.4mm difference over the rolling radius I think. The average rolling radius of a tyre that size is well over 2 metres I think, so pretty small %%s.

"within tolerances" is a phrase I like to use.

**JustinM3** · 05-02-2007,03:01 PM

Thanks for reply.
Tried to fit them to a calibra that runs 205/50 tyres, I banked on the width increase, but not the profile - the 2 combined meant tyre was too close to strut cup. I thought, as you say 'marginal' but was too close. Such little difference, but no room for the increase.

On neighbours car the front tyres are pretty close to strut cup, and wouldn't like to say if the extra 10 width would be do-able.

Good info though, but it's the physical aspect (tyre to strut) I'm concerned about - as you say within tolerance speedo wise, and would make it more accurate considering the built in overead.

Be nice if someone had these on their estate really!

Sure the Audi A4 1.8 sport thing will have 215's, is sportier, and remember them not looking too low profile at all.

Thanks for your help

**Sam** · 05-02-2007,03:02 PM

http://www.miata.net/garage/tirecalc.html

Simply plug the current tyres in the first boxes and the new ones in the second.

As for fit, they should fit fine. I have 205/60s on my 15s (ET 35ish) and they stand well away from the struts.

P Plate A4 is tricky to tell.

205/60/15 is the Euro standard (sometimes you'll find 195/65/15)

205/55/16, 225/45/17 and so on.

**JustinM3** · 05-02-2007,03:06 PM

Cheers.
All I need to know is whether they will safely fit - clear the strut, speedo etc is no concern.

**devonutopia** · 05-02-2007,05:17 PM

I say they will as you're not altering the width by much (a mere cm) and the profile is more or less the same too.

I went from 205/40 to 215/40 and whilst 40% is less than 55%, you cannot really tell I have different tyres on the front to the back. The difference on the road is much better though - could be because the front is a better model Toyo tyre too though.