Tyre pressures

[Dave1983]

Hi all,

 

I recently purchased an ex demo 2019 Superb Sportline plus from White Dove Skoda in Cardiff. It was the finance directors company car with 7k on the clock. First impressions have been really good apart from the road handling. It doesn't have DCC so just the standard Sportline shocks/ springs. Anyway after a few weeks of driving I have finally got round to checking things that I have read about on here like delivery blocks/ tyre pressures ect to explain the odd handling. I had a quick check of the shocks (didn't jack it up) but couldn't see any signs of the blocks, next I thought I would check tyre pressures and upon checking, all 4 tyres were pumped up to 42psi!! I checking what the correct pressures are and have now lowered them to 36psi and it has made a lot of difference on comfort and handling. 

 

What now concerns me is if they didn't check the tyre pressures what else didn't they check before I took delivery? I presume it should have had a PDI check prior to me picking it up, is this correct? and should I raise this with the dealership or leave as is?

 

Great full for any thoughts on this guys.

 

 

[Q102]

what do you mean by "odd handling"?

Understeer/oversteer, too bouncy or stiff suspension?

Edited 29 July, 2019 by Q102

[mandp]

I picked up my brand new car last Wednesday.

Once home I checked and saw that there are two different pressures...one `normal` and one `ECO`

Mine were pumped up to the `ECO` level which is much higher than `normal`.

I wonder if yours was the same?

[Tech1e]

They would have been way over 42 PSI before PDI. When was your tyre pressure gauge last calibrated?

[Bap33]

4 hours ago, mandp said:

I picked up my brand new car last Wednesday.

Once home I checked and saw that there are two different pressures...one `normal` and one `ECO`

Mine were pumped up to the `ECO` level which is much higher than `normal`.

I wonder if yours was the same?

The ECO setting is mainly different (higher) on the rear axle.

One thing to consider, is that ECO setting enables a slower wearing of the rear tires. With lower pressure, you'll get some facet wearig on the thread, which generates loud vibrations, which can be easily confiused whith the symptomatic noise of a 'dead' wheel ball beraing...

Thus don't hesitate to pump up to ECO values

[Dave1983]

On 29/07/2019 at 17:34, Q102 said:

what do you mean by "odd handling"?

Understeer/oversteer, too bouncy or stiff suspension?

It feels to bouncy, as if its way under damped, for instance if I drive over a speed hump which my 2010 superb sailed over the mk3 will almost bottom out and also feels like it rocks back to front after driving over the hump as if the shocks are not providing enough damping. Also on my way to work there is a small crest that I drive over which again in the 2010 superb was smooth but the mk3 bottoms out when it exits the crest. Also feels quite un-planted on rough corners like the shocks cant keep up with the bumps. might be me but it definitely does not feel like ''sport suspension'' so much so I have been looking at some Bilstein dampers. 

[Q102]

2 hours ago, Dave1983 said:

It feels to bouncy, as if its way under damped, for instance if I drive over a speed hump which my 2010 superb sailed over the mk3 will almost bottom out and also feels like it rocks back to front after driving over the hump as if the shocks are not providing enough damping. Also on my way to work there is a small crest that I drive over which again in the 2010 superb was smooth but the mk3 bottoms out when it exits the crest. Also feels quite un-planted on rough corners like the shocks cant keep up with the bumps. might be me but it definitely does not feel like ''sport suspension'' so much so I have been looking at some Bilstein dampers. 

They are bouncy and appear under damped, better with a bit of load on board. Does feel quite unsettled at speed on a bumpy road and my first vmax run on a German autobahn felt horrible- gave up at just over 100mph. On the way home with 6 crates of splendid German beer felt a lot happier.

I'd had my old XC60 upto 130mph on the same stretch and that was rock solid.

Next Superb will either have DCC or a sportline (think they have stiffer suspension)

EDIT having  seen again you have a sportline might not be best way to go🙃

Edited 2 August, 2019 by Q102

[Ootohere]

Friday Thought.

 

If the crap ECO type tyres that are fitted lower fuel consumption when the tyre pressures are up at ECO it must be due to less friction so less traction.

Less tread on the road as the pressure changes the profile.

?

Why do it to save a few pence per journey if the rain might come down and your traction / friction is already being reduced?

[Bap33]

@Roottootemoot If you increase tyre pressure, you effectiveley reduce the friction (less contact surface between tyre and road). BUT... Less contact surface, with same load, means higher pressure on the contact surface (Pressure = Force (e.g. load) / Surface).

This is why winter are narrower, to improve grip!

[Ootohere]

Really?   So on a wet road a narrow crap tyre is better than a wider crap tyre?  Sometimes maybe.

Better if you just go for the better tyres in the wet and at a sensible pressure then reducing tread on the tar IMO.

 

Do you do much offroading ?,

SAT tyres were narrow right enough,  Ice tyres, studded or just winters. 

Narrower to get through snow and get a grip maybe, in snow or mud,

or go wider when on to of snow like a Icelandic truck on a glacier and with low pressures. Flotation Tyres as well for the likes of Utility Vehicles.

 

Narrow tyres are better if not wanting to aquaplane on roads.  

 

I did go down to 265's instead of 285's for my CrossClimates, but that is not really narrow.

On lighter 4x4s i usually have 235's on for Winter / Snow.

Edited 2 August, 2019 by Roottootemoot