18" wheels to 16"

[ianbirch]

Hi all,

 

I wish to change my Pegasus 235/45/18 wheels to 205/55/16 on my 2016 Mk3 Superb

 

Can I do this and still maintain correct speed and mileage readings.

 

Regards Ian

[SurreyJohn]

No,

changing diameter from 669mm to 632mm so nearly 6% change on speedo

 

Not sure which engine you have, but 16 inch wheels should have 215/60 R16 (diameter only about 4mm less) or 0.6% (4mm diameter difference is more than acceptable as 2mm tread depth changes diameter by 4mm)

 

 

Edited 25 May, 2021 by SurreyJohn

[ianbirch]

 

1 minute ago, SurreyJohn said:

No, changing diameter from 669mm to 632mm so nearly 6% change on speedo

Thanks for the reply but i wondered if this could be compensated for in VCDS... how does the manurfacter deal with all the different wheel sizes they offer?

 

Regards Ian

[Ootohere]

By fitting the correct tyres to have the same or very close to the same Rolling Circumference / Diameter when the wheels are different diameters / widths.

 

https://tiresize.com/tyre-size-calculator

 

 

 

Edited 25 May, 2021 by e-Roottoot

[SurreyJohn]

4 minutes ago, ianbirch said:

 

Thanks for the reply but i wondered if this could be compensated for in VCDS... how does the manurfacter deal with all the different wheel sizes they offer?

 

Regards Ian

Yes there are codes that are set depending on wheel size, I’m sure someone has listed them in past.

 

However for 16 inch wheels, tyres are supposed to have a load rating of 95 and I suspect you won’t be able to get 205/55 R16 with a load rating of 95 (or higher)

 

[ianbirch]

Thanks very much for all the replies...very helpful....couple of things I hadn't thought of.

 

Regards Ian

[unclerichy]

If you haven't already done so make sure that 16s will fit over the brakes. Some Superbs won't take smaller than 17s

[paddywack1878]

can you swap the 17"stratos wheels to 19" sportline wheels without any problems?

[JBD1974]

Info here (Click ) may be of use. 

[Carlston]

7 hours ago, ianbirch said:

I wish to change my Pegasus 235/45/18 wheels to 205/55/16 on my 2016 Mk3 Superb

Can I do this and still maintain correct speed and mileage readings.

 

Skoda sell a 205/55R16 spare tyre to be used with the Superb MK3.

 

https://eshop.skoda-auto.cz/cs_CZ/rezervni-kola/c/spareWheels?q=%3AscoreDesc%3AcarType%3ASuperb%2BIII%2B%282015%2B%29&text=#

 

It's safe to use a 205/55R16 as long as you increase the tyre pressures compared to the standard tyre sizes.

 

If 205/55R17 uses 2.2 Bar (32psi) tyre pressure, you would need to use an extra 0.2 Bar tyre pressure with the lower load index 205/55R16, ie. 2.4 Bar (35psi).

 

This is because a 205/55R17 tyre with 32psi can support 491kg (670kg x 2.2/3), and a 205/55R16 tyre with 35psi can support 492kg (615kg x 2.4/3).

 

The only time that I wouldn't use a 205/55R16 standard load index tyre on a Superb MK3 is if you need to use more than 2.7 Bar (39psi). This is to give the tyre a big safety margin, as a standard load index car tyre has a maximum tyre pressure of 3 Bar (44psi). If you are going to use more than 2.7 Bar (39psi) tyre pressure, simply fit an XL tyre, which can be pumped up to 3.5 Bar (51psi), although again to have a big safety margin I wouldn't use more than about 3 Bar (44psi).

 

205/55R16 is the most common size car tyre sold in Europe, and is usually much cheaper than the standard Superb MK3 tyre sizes, such as 215/60R16, 215/55R17, etc.

 

Using 205/55R16 on a Superb MK3, the speedo will over-read by about 10%, as cars' speedos usually over-read by about 5% even on standard tyre sizes.

 

Edited 25 May, 2021 by Carlston

[paddywack1878]

On 25/05/2021 at 18:47, JBD1974 said:

Info here (Click ) may be of use. 

hi jb which page is applicable to me mate, there's hundreds of them.