The definitive tyre / wheel size thread
- Thread starter bretti_kivi
- Start date
Hi!
My current setup is:
Summer tyres: 175/65 R15 on original A2 alloy rims
Winter tyres: 155/65 R15 on original A2 steel rims
As I am rather dull, I want to get a second set of OEM steel rims to use in the summer too. This is because these wheels are much lighter than the alloys and make it less hassle to change from summer to winter tyres and vice versa twice a year. Also I am hoping the narrower profile will improve fuel economy (can anyone confirm ?) I can't seem to find any summer tyres available in 155/65 R15, but there seems to be a great deal of choice in 155/60 R15. So my question is, would it be OK to run 155/60 on the steel wheels or is it important to keep the 65mm height dimension ?
1,4 TDI 75kW 2005
My current setup is:
Summer tyres: 175/65 R15 on original A2 alloy rims
Winter tyres: 155/65 R15 on original A2 steel rims
As I am rather dull, I want to get a second set of OEM steel rims to use in the summer too. This is because these wheels are much lighter than the alloys and make it less hassle to change from summer to winter tyres and vice versa twice a year. Also I am hoping the narrower profile will improve fuel economy (can anyone confirm ?) I can't seem to find any summer tyres available in 155/65 R15, but there seems to be a great deal of choice in 155/60 R15. So my question is, would it be OK to run 155/60 on the steel wheels or is it important to keep the 65mm height dimension ?
1,4 TDI 75kW 2005
Jeff Sutcliffe
A2OC Donor
Jeff Sutcliffe
A2OC Donor
Tyre Size Calculator
A better easy to use tyre size calculator. Use our tyre size calculator to find tyre diameter, width, sidewall, circumference, and revolutions per mile.
As you can see in the chart below, the outside diameter of 155/60R15 is 4.1% smaller than 175/60R15. This is too big a difference. The speedo already over-reads by up to 5% on standard 175/60R15 tyres, so expect the speedo to over-read by close to 10% on these far too small tyres.
Also, the standard load index of 74(375kg) for the 155/60R15 might be too small for the weight of the Audi A2...especially the rear axle when fully loaded. Check that the maximum axle weights aren't more than 750kg...if so, a tyre with a 74(375kg) load index won't be able to support the weight.
Outside diameter of tyre
155/60R15 567mm (4.1% smaller outside diameter compared to 175/60R15)
175/55R15 573.5mm (3.0% smaller outside diameter compared to 175/60R15)
195/50R15 576mm (2.5% smaller outside diameter compared to 195/50R15)
155/65R15 582.5mm (1.4% smaller outside diameter compared to 175/60R15)
185/55R15 584.5mm (1.1% smaller outside diameter compared to 175/60R15)
205/50R15 586mm (0.8% smaller outside diameter compared to 175/60R15)
175/60R15 591mm
165/65R15 595.5mm (0.8% bigger outside diameter compared to 175/60R15)
195/55R15 595.5mm (0.8% bigger outside diameter compared to 175/60R15)
155/70R15 598mm (1.2% bigger outside diameter compared to 175/60R15)
185/60R15 603mm (2.0% bigger outside diameter compared to 175/60R15)
205/55R15 606.5mm (2.6% bigger outside diameter compared to 175/60R15)
175/65R15 608.5mm (3.0% bigger outside diameter compared to 175/60R15)
195/60R15 615mm (4.1% bigger outside diameter compared to 175/60R15)
185/65R15 621.5mm (5.2% bigger outside diameter compared to 175/60R15)
With the standard 15" steel rims, there's a choice of 5Jx15 ET28 5/100 57.1 and 5.5Jx15 ET34 5/100 57.1
The 155/65R15 winter tyre size was fitted to the 5J rim as standard and the 175/60R15 was fitted to the 5.5J rim as standard. The 165/65R15 might have been fitted to the 5.5J rim as standard, although my preference would be the 5J rim for this tyre size.
Also, the standard load index of 74(375kg) for the 155/60R15 might be too small for the weight of the Audi A2...especially the rear axle when fully loaded. Check that the maximum axle weights aren't more than 750kg...if so, a tyre with a 74(375kg) load index won't be able to support the weight.
Outside diameter of tyre
155/60R15 567mm (4.1% smaller outside diameter compared to 175/60R15)
175/55R15 573.5mm (3.0% smaller outside diameter compared to 175/60R15)
195/50R15 576mm (2.5% smaller outside diameter compared to 195/50R15)
155/65R15 582.5mm (1.4% smaller outside diameter compared to 175/60R15)
185/55R15 584.5mm (1.1% smaller outside diameter compared to 175/60R15)
205/50R15 586mm (0.8% smaller outside diameter compared to 175/60R15)
175/60R15 591mm
165/65R15 595.5mm (0.8% bigger outside diameter compared to 175/60R15)
195/55R15 595.5mm (0.8% bigger outside diameter compared to 175/60R15)
155/70R15 598mm (1.2% bigger outside diameter compared to 175/60R15)
185/60R15 603mm (2.0% bigger outside diameter compared to 175/60R15)
205/55R15 606.5mm (2.6% bigger outside diameter compared to 175/60R15)
175/65R15 608.5mm (3.0% bigger outside diameter compared to 175/60R15)
195/60R15 615mm (4.1% bigger outside diameter compared to 175/60R15)
185/65R15 621.5mm (5.2% bigger outside diameter compared to 175/60R15)
With the standard 15" steel rims, there's a choice of 5Jx15 ET28 5/100 57.1 and 5.5Jx15 ET34 5/100 57.1
The 155/65R15 winter tyre size was fitted to the 5J rim as standard and the 175/60R15 was fitted to the 5.5J rim as standard. The 165/65R15 might have been fitted to the 5.5J rim as standard, although my preference would be the 5J rim for this tyre size.
Last edited:
A2Z
A2OC Donor
My first question to you would be how do you find the oversized 175/65/15 tyres on your current summer wheels?
My reason for asking is that first hand actual physical experience is far better than quoting lots of online figures and baffling you with science (of which there is an awful lot when you really delve into wheels/tyres) and the effect they can have on a car, both positively and negatively.
You can quite easily ruin the ride quality of a car or conversely totally transform it by fitting the right or wrong combination of wheels and/or tyres.
My advice is never to go smaller in rolling circumference than the factory size tyres as, one, this will normally result in a loss of comfort (more so if you use too high of a load index) and two, your Speedo with over-read more than it does already which is normally 3 to 3.5mph @ 70mph from the factory this being more inaccurate.
I am also not normally a fan of steel wheels (partly because they rust and secondly there is nothing worse than seeing them wobble along when the wheel trims/hub caps aren't fitted properly) but I must admit that I do like the look of the A2 steels (with the wheel trims fitted) as they suit the simplicity and ethos of the A2. That said they are not aluminium and the factory forged aluminium A2 15" alloys are just perfect on the A2 in my opinion and offer the best ride of any wheels I've ever used. With oversized 175/65 tyres they are like riding on Aladdin's magic carpet!
To answer your question, definitely don't buy 155/60/15 as they are way too small (although they would make the car feel very nippy when pulling away as they would lower the gearing) but my advice would be 165/65/15 or if you want as narrow as possible go 155/70/15 if they are available but personally I wouldn't go narrower than 165 for summer tyres as you want a reasonable amount of contact with the road for grip, where as winter tyres are ideal to be as narrow as possible to cut through the snow.
I also don't believe you would achieve much (if anything) regarding better mpg and I think this could be best improved by selecting the right tyres with the best fuel efficiency rating (check the tyres labels for the information).
If you take a look at this site it gives you all the information you could need to see the real term effects of changing sizes from the standard 175/60/15 A2 size which you can do by altering the sizes on the lower chart.
Hope this helps you make your decision a little
Alloy Wheel & Tyre Fitment Calculator. Offset, Tyre Stretch and Speedo Error | Will They Fit
Alloy Wheel & tyre fitment calculator - it calculates inset, poke, speedo error, tyre stretch and loads more.
www.willtheyfit.com
Thanks very much for your knowledgeable reply. Very interesting to learn that one should not go under the original tyre diameter. This definitely helps me in the decision process. The wheel/tyre calculator is just what I have been looking for too. Cheers!My first question to you would be how do you find the oversized 175/65/15 tyres on your current summer wheels?
My reason for asking is that first hand actual physical experience is far better than quoting lots of online figures and baffling you with science (of which there is an awful lot when you really delve into wheels/tyres) and the effect they can have on a car, both positively and negatively.
You can quite easily ruin the ride quality of a car or conversely totally transform it by fitting the right or wrong combination of wheels and/or tyres.
My advice is never to go smaller in rolling circumference than the factory size tyres as, one, this will normally result in a loss of comfort (more so if you use too high of a load index) and two, your Speedo with over-read more than it does already which is normally 3 to 3.5mph @ 70mph from the factory this being more inaccurate.
I am also not normally a fan of steel wheels (partly because they rust and secondly there is nothing worse than seeing them wobble along when the wheel trims/hub caps aren't fitted properly) but I must admit that I do like the look of the A2 steels (with the wheel trims fitted) as they suit the simplicity and ethos of the A2. That said they are not aluminium and the factory forged aluminium A2 15" alloys are just perfect on the A2 in my opinion and offer the best ride of any wheels I've ever used. With oversized 175/65 tyres they are like riding on Aladdin's magic carpet!
To answer your question, definitely don't buy 155/60/15 as they are way too small (although they would make the car feel very nippy when pulling away as they would lower the gearing) but my advice would be 165/65/15 or if you want as narrow as possible go 155/70/15 if they are available but personally I wouldn't go narrower than 165 for summer tyres as you want a reasonable amount of contact with the road for grip, where as winter tyres are ideal to be as narrow as possible to cut through the snow.
I also don't believe you would achieve much (if anything) regarding better mpg and I think this could be best improved by selecting the right tyres with the best fuel efficiency rating (check the tyres labels for the information).
If you take a look at this site it gives you all the information you could need to see the real term effects of changing sizes from the standard 175/60/15 A2 size which you can do by altering the sizes on the lower chart.
Hope this helps you make your decision a little
Alloy Wheel & Tyre Fitment Calculator. Offset, Tyre Stretch and Speedo Error | Will They Fit
Alloy Wheel & tyre fitment calculator - it calculates inset, poke, speedo error, tyre stretch and loads more.
A2Z
A2OC Donor
I forgot to mention that I think the weight difference you mention between your winter and summer wheels will mostly be down to the tyres too as the factory 5.5j forged alloys are almost featherweight (much like the 6j Pepperpots). I haven't compared the weight difference between them and the Steel's personally but think it would be minimal but I'm sure the weights would be on here somewhere if you have the time to research.
You could also fit whichever width of tyre you decide upon to the factory alloys too if you wanted to.
Also feel free to post on here what you're contemplating buying before you do so if you are at all unsure and we can advise what we think might suit best
Hi,
I use 165/70 14 for my car.
As many others say, rolling distance affect your speedo reading.
I used to own 2008 BlueMotion 1.4 Polo TDi which has this tyre size. The car was heavier than A2 and drove like it was on the rail.
VAG has spent many hours perfecting the balance of grip, road holding, comfort and so on. So I went with 14" Polo wheels with this size tyre.
Unsprand weight has reduced and road holding hasn't lost, if anything better suspension feel as I have Bilstein shocks.
The ride comfort has improved but using All season tyres for mine, no improvement in economy.
I use 165/70 14 for my car.
As many others say, rolling distance affect your speedo reading.
I used to own 2008 BlueMotion 1.4 Polo TDi which has this tyre size. The car was heavier than A2 and drove like it was on the rail.
VAG has spent many hours perfecting the balance of grip, road holding, comfort and so on. So I went with 14" Polo wheels with this size tyre.
Unsprand weight has reduced and road holding hasn't lost, if anything better suspension feel as I have Bilstein shocks.
The ride comfort has improved but using All season tyres for mine, no improvement in economy.
Can now also confirm that 195/55R16 does not rub with H&R lowering springs
A2Z
A2OC Donor
Important to say on what rims (width/J and offset/ET) as that size is on the limit and will rub on some and possibly not on others.
Do you have rear mudflaps fitted as they must be very close to those too?
A2Z
A2OC Donor
Would you be able to post a photo of the rear wheel face on please, would be good for reference?.
I've used oversized 185/55/16 tyres on standard 6J ET35 SE alloys and they were pretty close to the rear mudflaps so your even larger 195/55/16 must be very close indeed.
I see now from your photo you're running the 7J ET34 A1 Sport 16's, they look good
Would you be able to post a photo of the rear wheel face on please, would be good for reference?.
I've used oversized 185/55/16 tyres on standard 6J ET35 SE alloys and they were pretty close to the rear mudflaps so your even larger 195/55/16 must be very close indeed.
I see now from your photo you're running the 7J ET34 A1 Sport 16's, they look good
There is a inch or 2-3 cm clearance
lavandism
Member
offtopic, but it is amazing how you can make A2 look like a proper little SUV with right ingredients
(and not just safari-fied hatchback)
trevorswaine
Member
lavandism
Member
Alfa 156 wheels? Spacers or it a bit of stubbornness and a strong hand?