How to make Skoda Superb MK3 more cofortable

[mikonk]

About 6 months ago I bought a new Skoda Superb 2.0 TDI 190hp DSG The car is completely ok, extremely spacious and for these 10k as I went for these 6 months I did not notice any major flaws other than sensitivity to bumps in the road.

What is it about? The car feels even the slightest bump in the road.. I tried to change the tires, to put the height, ie instead of 235/45/18 I put 235/50/18 but it did not have any effect, while for example on the winter continental it was quite decent.

Now I'm wondering if you have experience with this, has anyone tried to solve it by changing the tires or shock absorbers ...?

Does anyone perhaps have a recommendation of what tire size to put on the vehicle to make it more comfortable ?

In my opinion for this class of vehicle it is extremely uncomfortable...

 

Thanks in advance

[Carlston]

Is your winter tyre size 215/55R17 ?

 

One of the problems affecting the ride comfort is the wide 8J rims which you may have fitted as standard.

 

235/50R18 could be fitted to much narrower 6.5J or 7J rims. By fitting them to 8J rims you are stretching the sidewalls which makes the sidewalls flex less easily, and thereby transmitting more of the bumps to you.

 

For comfort, it's also important to choose tyres that have soft, flexible sidewalls. If you are fitting UHP (Ultra High Performance) summer tyres, then these tend to have stiff sidewalls because they are not made for comfort but for handling.

 

Skoda do sell slightly narrower 7.5J 18" rims, in anthracity and silver.

 

TRINITY alloy rims 7.5Jx18 ET46

https://eshop.skoda-auto.cz/cs_CZ/kolo-z-lehke-slitiny-trinity-18-pro-superb-ii-octavia-iii-scout/p/3T0071498A+HA7

https://eshop.skoda-auto.cz/cs_CZ/kolo-z-lehke-slitiny-trinity-18-pro-superb-ii-octavia-iii/p/3T0071498J+8Z8

 

235/45R18 has a load index of 94 (670kg) @ 3 Bar (44 psi)

235/50R18 has a load index of 97 (730kg) @3 Bar (44 psi)

 

Did you lower your tyre pressures by 0.2 Bar (3 psi) when you changed from 235/45R18 to 235/50R18 ? If not, that would go a long way to explaining why you didn't notice much difference in ride comfort.

 

A 0.2 Bar (3 psi) difference in tyre pressure is easily noticeable.

 

If you want to try out some cheap 7.5Jx18 ET50 steel rims, then these are the size of the ones used on the VW ID.3 electric car.

 

Alcar 9383 7.5Jx18 ET50 Steel Rims

https://www.oponeo.pl/felga-stalowa/alcar-kfz-9373#21889193

 

7.5J is ok for 235/50 tyres, and is really as wide as you would want to go. It's like fitting 195/50 tyres to 6.5J rims.

 

Uniroyal Rainsport 5 235/50R18 97V might be softer riding than what you have now

https://www.mytyres.co.uk/rshop/tyre/Uniroyal/RainSport-5/235-50-R18-97V/R-402383

 

For maximum comfort, it's important not to have a higher speed rating than you need, or XL (eXtra Load) if you don't need it.

 

For example, 235/50R18 97V instead of 235/50R18 101Y for the Superb MK3 190HP, as the car doesn't go over 240km/h (150mph) and doesn't need tyres with a higher load index than 97.

 

Skoda Superb 2020 2.0TDI 190HP

 

Tire	Rim
235/45ZR18 94W	8Jx18 ET44	2.4 / 2.2
235/40ZR19 96W	8Jx19 ET44	2.5 / 2.3

 

Edited 24 April, 2021 by Carlston

[mikonk]

20 minutes ago, Carlston said:

Is your winter tyre size 215/55R17 ?

 

One of the problems affecting the ride comfort is the wide 8J rims which you may have fitted as standard.

 

235/50R18 could be fitted to much narrower 6.5J or 7J rims. By fitting them to 8J rims you are stretching the sidewalls which makes the sidewalls flex less easily, and thereby transmitting more of the bumps to you.

 

For comfort, it's also important to choose tyres that have soft, flexible sidewalls. If you are fitting UHP (Ultra High Performance) summer tyres, then these tend to have stiff sidewalls because they are not made for comfort but for handling.

 

Skoda do sell slightly narrower 7.5J 18" rims, in anthracity and silver.

 

TRINITY alloy rims 7.5Jx18 ET46

https://eshop.skoda-auto.cz/cs_CZ/kolo-z-lehke-slitiny-trinity-18-pro-superb-ii-octavia-iii-scout/p/3T0071498A+HA7

https://eshop.skoda-auto.cz/cs_CZ/kolo-z-lehke-slitiny-trinity-18-pro-superb-ii-octavia-iii/p/3T0071498J+8Z8

 

235/45R18 has a load index of 94 (670kg) @ 3 Bar (44 psi)

235/50R18 has a load index of 97 (730kg) @3 Bar (44 psi)

 

Did you lower your tyre pressures by 0.2 Bar (3 psi) when you changed from 235/45R18 to 235/50R18 ? If not, that would go a long way to explaining why you didn't notice much difference in ride comfort.

 

A 0.2 Bar (3 psi) difference in tyre pressure is easily noticeable.

 

If you want to try out some cheap 7.5Jx18 ET50 steel rims, then these are the size of the ones used on the VW ID.3 electric car.

 

Alcar 9383 7.5Jx18 ET50 Steel Rims

https://www.oponeo.pl/felga-stalowa/alcar-kfz-9373#21889193

 

7.5J is ok for 235/50 tyres, and is really as wide as you would want to go. It's like fitting 195/50 tyres to 6.5J rims.

 

Uniroyal Rainsport 5 235/50R18 97V might be softer riding than what you have now

https://www.mytyres.co.uk/rshop/tyre/Uniroyal/RainSport-5/235-50-R18-97V/R-402383

 

For maximum comfort, it's important not to have a higher speed rating than you need, or XL (eXtra Load) if you don't need it.

 

For example, 235/50R18 97V instead of 235/50R18 101Y for the Superb MK3 190HP, as the car doesn't go over 240km/h (150mph) and doesn't need tyres with a higher load index than 97.

 

Skoda Superb 2020 2.0TDI 190HP

 

Tire	Rim
235/45ZR18 94W	8Jx18 ET44	2.4 / 2.2
235/40ZR19 96W	8Jx19 ET44	2.5 / 2.3

 

 

Thanks Carlston for detailed answer.

 

My winter tires is Continental 235/45/18.

 

Now on my Superb is Uniroyal Rainsport 5 235/50R18 97V, but this is little slipping  tire, I am nnot happy with it when it comes to sliding braking. Last summer tires Continental PC 235/45/18 is much better for braking, but so hard on bumps.

 

I have no requirements for fast driving, mostly my is driving from 80km/h - 110 km/h on open road (Here we have no highways and most of the roads are of poor quality)

 

I read that the Michelin Primacy 4 is a soft tire and that it is comfortable, what do you think about that, in the dimension 235/45/18? 

 

Last solution is to move on dimension 17 inch, but with that dimension the car is a little "ugly", or refitt some DCC or another suspension, but I still dont know which

 

[KenONeill]

@Carlston @mikonk 8.0J wheels are 203.2mm wide. In no way is running those wheels with 235 tyres "stretch", which is running wheels that are wider than the tyres. A statement like that makes me question the rest of post 2 as well.

[dieselV6]

17in 6.5J wheels with quiet 215/55/R17 tyres (can be all season eg Cross Climates, or whatever you fancy, just with low noise rating), harmonic balancer on rear subframe, and polyethylene boot tray (the shallow one like here  or cheaper on ebay).

Also, acoustically damping carpet underlay in the spare wheel well helps too.

 

You can also keep current wheels and see if the harmonic balancer and the boot tray (and possibly carpet underlay) will make things good enough for you.

 

[Angelo Amato]

Shock absorbers are well documented on this group and provided me the information I required to make the decision to 'fix' mine. New shocks on (Koni) and it's so much nicer to drive.

 

Was the only thing letting a great car down.

 

Angelo

[Carlston]

2 hours ago, KenONeill said:

8.0J wheels are 203.2mm wide. In no way is running those wheels with 235 tyres "stretch", which is running wheels that are wider than the tyres. A statement like that makes me question the rest of post 2 as well.

 

As you can see below, 7.5J is the normal rim width for a 235/50R18 tyre. 6.5J and 7J would give the most comfortable ride, with 8J and 8.5J giving the least comfortable ride because the sidewalls are being stretched.

 

Tyre Size				Approved Rim Width Range (inch)
235/50R18				6.5-7.5-8.5

 

https://www.toyo.co.uk/tirefinder/index/width/235/aspect/50/rim/18

 

Edited 24 April, 2021 by Carlston

[KenONeill]

@Carlston - The fact that you are choosing to define the word "stretch" differently to everyone else in respect of wheel and tyre fitments does not make me wrong.

 

Your actual technical point about ride comfort as you vary wheel sizes with a particular tyre size was never disputed.

[facet edge]

On 24/04/2021 at 11:31, mikonk said:

I tried to change the tires, to put the height, ie instead of 235/45/18 I put 235/50/18 but it did not have any effect

Wouldn't increasing the sidewall mean the speedometer would read incorrectly?

An indicated speed of 60kph would be a real speed of 62.5kph

[Carlston]

4 minutes ago, facet edge said:

Wouldn't increasing the sidewall mean the speedometer would read incorrectly?

An indicated speed of 60kph would be a real speed of 62.5kph

 

The speedo over-reads by about 5% on standard tyres, so fitting oversize can actually make the speedo more accurate.

 

It's easy to check with google maps, as that can be used as a very accurate gps speedo.

[facet edge]

1 minute ago, Carlston said:

 

The speedo over-reads by about 5% on standard tyres, so fitting oversize can actually make the speedo more accurate.

 

It's easy to check with google maps, as that can be used as a very accurate gps speedo.

That may be so but you probably invalidated your insurance by fitting that size tyre.

[Ootohere]

  So the indicated 60kph is more likely to be around 57.5kph.     The insurance thing often arises. 

But then many fit tyres that are approved sizes and many have tyres larger and declared modifications. 

That will be the 4x4's and the likes you see driving around.

Edited 29 April, 2021 by e-Roottoot

[facet edge]

https://tire-calc.com/comparison/235-45-r18-and-235-50-r18/

 

The diameter is larger so you will be covering more ground per revolution, e.g. going faster than indicated.

 

As you say you have to have insurance approval of you fit non standard size tyres.

Edited 29 April, 2021 by facet edge

[Ootohere]

As pointed out to you from the factory the speedo over reads on OEM fitted tyres. 

The bigger circumference tyres will have the actual indicated speed nearer to accurate.

 

Those that are used fitting and using larger tyres will usually know how much bigger has them not with the speedo 'under reading'. 

 

It is not rocket science and pretty easy to know what is what.   The Tyre Size Calculators are good, but when you get tyres from different manufacturers maybe run a tape measure around the circumference of the tyres with them on a rim and inflated.

Maybe compare different brands and types of the same 'marked sizes',  and compare brand new ones against worn tyres.