Cheap handling improvements.

[Steve Walker]

I spent this weekend at the track trying to get rid of the tyre shredding understeer which has been affecting the squealmobile recently (see photos of tyres) We upped the tyre pressures gradually from standard to 2.9 bar front & rear and the transformation was stunning. Far less understeer & a much more fixed feeling in the 100mph plus corners. The back end felt stable with cotrollable drifting possible.

I was going to lower & stiffen but don't think I will bother now.

I also swapped disks & pads for new standard bits & the brakes are now fine. No fade, good feel & plenty of power to make the ABS come in when required.

[bengie]

good news!

might want to edit your pic to take the number plate out mate

[Mil]

So basically, the higher the psi, the better the handling?

[pbirkett]

Sort of makes sense, especially considering that big lump of pig iron up front.

[rsbspt]

42psi front and rear - wow that's hard! Ride must be rock solid. OK for the track but not much use for the road I imagine...

[Sallyann]

So basically, the higher the psi, the better the handling?

Surely there is more to it than that? There must be a good reason for the recommended pressures.

Sal

[bengie]

upto a point, trouble is thecar will start hopping on corners

[Steve Walker]

So basically, the higher the psi, the better the handling?

On the stock pressures the front tyres were distorting badly as you can see from the wear on the side walls. At the higher pressure the tyres feels much stiffer in the side wall & the understeer doesn't come in so soon. We swapped tyres front to back & looked at the wear pattern with the higher pressure & you can see that the tyre isn't rolling off the rim so much.

I don't know what the best pressure is yet but if we had carried on with the stock pressure we would have been through to the canvas on the side walls soon.

The most noticeable change is that she stopped squealing at every corner until we upped the speed again

[a14nsh]

Will the tyres not wear prematurely in the middle of the pattern?

[BLiND]

Very interesting this, I often find having tyres higher than the "standard" pressures they feel more stable.

On the point of wearing in the middle... yeah they will if you run 42psi on the roads!... this was on the track, totally different scenario. All this is saying is, that slighty higher pressures will help with turn-in.

Me personally, I think running 36psi front for the road would be acceptible.

p.s. please bear in mind that the likelyhood of the tyres breaking-away quickly is higher, at higher pressures... at lower pressures they will skid more, and give a more gradual loss of traction... which may be less fun, but its safer!

[Steve Walker]

Will the tyres not wear prematurely in the middle of the pattern?

Theoretically yes if we were driving slowly on the road with a minimum load but at track speeds the wear patterns are totally different. With the standard pressures we would have gone through the sidewall with 6mm of tread still left in the centre. I revert to normal pressures for the road but I never drive it hard enough on the road to explore its handling at the limit.

Skoda advise different pressures if carrying a full load anyway so we are not completely "out of the envelope" & my comments only apply to the tyres I have, Conti 2s. Others may have stiffer sidewalls.

[Steve Walker]

Very interesting this' date=' I often find having tyres higher than the "standard" pressures they feel more stable.

On the point of wearing in the middle... yeah they will if you run 42psi on the roads!... this was on the track, totally different scenario. All this is saying is, that slighty higher pressures will help with turn-in.

Me personally, I think running 36psi front for the road would be acceptible.

p.s. please bear in mind that the likelyhood of the tyres breaking-away quickly is higher, at higher pressures... at lower pressures they will skid more, and give a more gradual loss of traction... which may be less fun, but its safer![/quote']

I agree totally John. With the lower pressures the car was a drifting dream but would scrub off so much speed that fast wasn't possible. Great sound though! We did try even higher pressures but it was very twitchy. The final settings were a compromise but more work may prove even more useful. I may try to lower the rears slightly but keep the fronts high next time.

The improved stability was very noticeable in fast twisters.

[boyced]

from standard to 2.9 bar front

we noticed that after a few laps the typre pressure increased due to the increase in tyre temp!

[pbirkett]

I agree totally John. With the lower pressures the car was a drifting dream

Drift or understeer? I suspect the latter, since I never ever managed to "drift" my Fabia vRS when I had it, and it wasnt for the lack of trying.

[bengie]

you can't drift a FWD car, its impossible. you need power at the rear to drift.

oversteer maybe but drift no

[Shifty]

If anybody is interested, i run 36 psi all round on my fabia vrs. at 32 psi, there was too much give in the sidewalls and the back end dug in on corners making the understeer worse. since i played with the pressures, i find 36psi to be the optimum, giving a crisper ride, sharper turn in, and a slightly unsettled rear which lessens the understeer slightly, especially if you use the throttle to help steer the car. Having said this, i haven't yet managed any serious oversteer.....maybe i need to try harder or get bigger bo//ocks?

[richarde]

I played with the pressures a while back on the standard contis. Anything much over 36psi in the wet and the understeer was horrific as was braking, unless fully committed that is. Must be the reduced contact patch. In the dry on twisties though it was a different matter..

[Steve Walker]

you can't drift a FWD car' date=' its impossible. you need power at the rear to drift.

oversteer maybe but drift no[/quote']

What I mean by drifting is the classic 4 wheel drift rather than the modern sport of just power sliding the back end.Basically front & back sliding at the same time

If I want just to have the back end sliding all I have to do is lift mid corner & it steps out in a very dramatic fashion. Too dramatic for me actually!

[jtstatic]

IMO the recommended pressures are way too low even for everyday road use (talking about 205/45 size). Esp. on bad quality tarmac the sidewalls don't feel stiff enough if you run into sharp bumps. I don't know about England but here in Finland we have lot of medium/bad quality roads and that's usually where all the best twisties are 2.9 bar is maybe a bit high for everyday use (may be good for track though) but I personally think something like 2.5-2.7 would be good depending on your driving style. I usually use 0.2bar less @ rear if the car is empty as there is more weight @ front.

[ColinD]

you can't drift a FWD car' date=' its impossible. you need power at the rear to drift.

oversteer maybe but drift no[/quote']

iFor the fans of a certain Ninja site...in the guise of Tolkein...one does simply not walk into Mordor...

er yes you can...

Perhaps not as well as a RWD car, but it's possible. Also as Steve points out the "rwd" powered drift is one variant, 4 wheel drift is another and ffelan has another .

Now where's fifi when I need his vid

[redbaron]

http://www.wlnet.co.uk/Pages/Videos.htm

[Steve Walker]

I was playing again last night & finally had a chance to measure cold pressures before starting out. We are currently running 2.7 bar measured at 18deg C ambient before driving the car. This climbs to 3.0 measured after a few laps with the tyres very hot

At a corner, Fuchsrohre, where I was lifting at 110mph last week on standard pressures ,I was taking confidentally at 120mph which was full throttle. The car just felt planted . Last week you could feel the tyres moving on the rims.

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new tyres paul