Sodding Understeer / Winter Preps

[Wee-nemo]

That time of the year again, was starting to lose grip in the wet on the stock Potenzas so I thought I'd switch to the winter set. Of course the average temperatures aren't quite below 7C yet so a little slidyness was expected, but it's SO BAD that I'm fed up of having them on already. There's still a fair amount of tread on each set (6-7mm) as each have only done about 6 months duty, but the car goes round roundabouts right now like its on marbles at anything over a jogging pace with more than a few degrees of steer on, and feels floaty on sweeping bends with negligible feedback from the wheel.

I know some people have had success curing this models rampant understeer with major suspension adjustment but this isn't an option for me while the car is under warranty and finance. I wonder whether the tyre pressures could be adjusted and would be grateful if anyone has an idea about what they should be set to. I'm running winter tyres (Nokian A3s) of size 215/40/R17, same as the stock tyres and on stock alloys, with a normal light duty summer inflation of 2.5B (36psi) front and 2.0B (29psi) rears. I'm guessing over inflating them would only make the problem worse, not least because the last time I had these tyres on the garage massively overinflated them and they felt much the same, no grip when setting off or going round tight bends, until I discovered why a couple of days later - and yes, I have checked and rechecked the pressures all round this time!

The tyres I know are excellent when it gets really cold, as I've had sets on each of my last 3 cars and they've never let me down in heavy rain or snow. It just seems to be this time probably as a combination of putting them on when it's still above their working temperature, and th cars understeering characteristic.

Oh, and has anyone with the HIDs found they point far too low to light up the road sufficiently? I've noticed it for a long while but it's only become a problem again as sunset gets earlier in the day. My last car had them and they seemed set at a higher angle to illuminate further down the road, wondered if there was a way of manually adjusting their set point, or if this is a VCDS thing only?

 

[Wee-nemo]

Interestingly, and contrary to what I thought, the manual says that for winter tyres all pressures must be set 0.2B higher than the figures specified on the loading sticker on the fuel flap. Suppose that's to counter higher air density at lower temperatures, doesn't help much when the contact patch is already insufficiently grippy as it is though!

 

[Pyrres]

Higher pressures help a lot but the physics dont change. Im actually running almost 3bars in every corner but then again I have 185/60x15 wintertires.

And I noticed the same thing about the xenons. Got them checked and I checked them also and they actually point exactly where they are supposed to but they dont emit any light outside the beams area. And thats annoying as hell. The good thing is that high beam is as good as it gets. So no worries there.

Sent from my HTC One_M8

 

[Ahl]

I reckon 36 psi is far too high on even standard tyres on these cars.

Try reducing the front pressure and increasing the rear.

 

[Pyrres]

I reckon 36 psi is far too high on even standard tyres on these cars.

Try reducing the front pressure and increasing the rear.

As an ex mechanic I can assure you, its not too much. Normally people put way too little pressure to their tires. Tire technology has gone forward and they now need higher pressures.

Sent from my HTC One_M8

 

[Wee-nemo]

I've out a straight edge across the width of each tyre, the contact patch is flat and not bowed as thought it was overinflated. I'll try upping as per the manufacturers recommendations but not expecting miracles. Here's the only guy in Scotland wishing it to get colder sooner!

That's mostly the problem with the headlights, there's a crisp defined area of light and nothing beyond it. Im loathe to use full beams if I can help it as I inevitably end up headlight jousting with another car coming the other way every minute or two

 

[RUM4MO]

I've out a straight edge across the width of each tyre, the contact patch is flat and not bowed as thought it was overinflated. I'll try upping as per the manufacturers recommendations but not expecting miracles. Here's the only guy in Scotland wishing it to get colder sooner!

I've also converted for winter running, this will always happen if you try to push on a bit when the temperature is too high for them, also you have chosen to go against the normal logic of using narrower tyres in winter that is also helping to make things nasty, finaly yes, as said many times before, modern winter tyres need a bit more pressure in them.

I've stuck with normal European type winter tyres, ie Michelin Alpin and Alpin Pilots, unfortunately I'm travelling down to Kent for Christmas, so if the weather is still "far too warm" I'll need to go easy in my S4, though these tyres do like torrential rain!

 

[Wee-nemo]

I didn't want to fall foul of warranty or finance restrictions and putting narrower wheels on would unfortunately be classed by both as a modification. I've had great success using winter tyres on my previous cars with no reduction in tyre width, just seems much looser this time, even more so than when I last had these tyres on at the end of last winters season.

 

[RUM4MO]

I didn't want to fall foul of warranty or finance restrictions and putting narrower wheels on would unfortunately be classed by both as a modification. I've had great success using winter tyres on my previous cars with no reduction in tyre width, just seems much looser this time, even more so than when I last had these tyres on at the end of last winters season.

I know it can become messy, but ironically, I'd hope if you chatted to your insurance company they would be quite happy with you fitting whatever is Seat's homologated winter sized tyres and wheels.
Now if Seat have not sought approval for these cars to get used with more suitable winter tyres/wheels, then they should not be allowed to sell these cars for "all season" use in UK and other countries where it snows and gets a bit cold.
Changing to smaller narrower wheels and tyres in winter happens all over Europe, so if your finance and warranty providers do not like that then see above wrt Seat, this is the real world!
For what it is worth, my S4 is approved to run smaller narrower winter tyres, but also gives figures for using the normal sized 18" option with correct sized 18" M+S tyres - maybe not the ideal winter tyre size but a good enough compromise between look/grip for me, and still correct enough to be complying with homologated sizes.

 

[Wee-nemo]

I've stuck a bit more pressure into the tyres, now running 2.7B fronts and 2.3B rears, between that and the temperatures falling slightly (around 8C during the days here) over the last couple of days the car is tending to grip more on roundabouts. Don't know whether that's principally down to the pressure or the ambient temperature but suspect it's more the latter. Happy either ways though.

Having run the last few years on stock tyre sizes rather than drop to a narrower tyre for winter, I can say I haven't had any problems with the wider tyre in all weather conditions, from thick snow to heavy rain. I believe it's only snow where narrower tyres are supposed to make a difference, presumably a bigger contact patch from wider tyres would be more beneficial on a wet road. Since british winters involve many more wet days than occasional snowy ones - even up here in rural scotland - I think the better compromise would be sticking with a bigger size for road holding in the wet and putting up with having to travel slightly slower to remain safe in snow. I guess when you're stuck behind this lot every time it won't make too much difference anyway



Either way it should be noted, it's far safer to have any kind of winter tyre on than none at all!

 

[Wee-nemo]

As a follow-up, here are my recent experiences from these tyres. Been working away for a few weeks and came home a couple of nights ago to snow and slush lying on the roads, at an indicated temperature of around 1degC, tyres felt much more grippy and coped excellently allowing overtakes on the unused snowy lane of the dual carriageway without ever feeling insecure.

As mentioned before, the only problem with having winter tyres on is that you still have to slow down for the d***heads that didn't put them on and are fighting the wheel to not spin off at 30mph along the ungritted B road near my village. As it was, I could sit at a comfortable 50 when past these clowns and induce a little tail slide on demand when turning into my road on the home stretch. Happy days!

Think it was probably just the warmer temps that were causing the problems a few weeks ago, during the warmer days the road holding feels less secure (compared to my last car at least) but manageable.

 

[RUM4MO]

And this morning further down near Edinburgh, it was +10C when I was driving into work at 06:30! Which was good as I was using Beezer with (wide) summer tyres on!!