Tyre pressures

[nickboazracing]

I would do a few fast laps, come in and let them back down to that.

I think this is the key for trackdays. Keep an eye on them all day really. They should go up in the morning as you get initial heat in the tyres, then slowly as track temp goes up, then as the track cools off later in the afternoon you'll see the pressures drop slightly. You'll prob have to reset them for the drive home too, with the lefts prob being a bit lower after the tyres have cooled down.

So what do people run in PE2's for trackdays? I'm off to Silverstone, hopefully Tuesday evening, GP circuit 8)

 

[480bhp.com]

I've spent many years around the pits and paddocks of various circuits, but my knowledge on the clio is limited to just 4 trackdays this year. While my findings so far may not be what needs to be run, there a base from which i'm currently working. Also remember these settings are based around 15-30 sessions on the track at a reasonable pace.

Pe2's
32 psi front cold
30 psi rear cold

This helps prevent the edges being scrubbed away, although i run 2.5 degrees of negative camber and this also helps
pressure any lower doesn't seem to significantly improve grip, but tyre life is dramatically reduced.

R888's

30 psi front cold
28 psi rear cold

These pressures are still not right, but are a reasonable place to start from, I've also tried as low as 24/25 psi in the fronts and a similar pressure in the rear, the rears were fine at this lower pressure, but the fronts were terrible, overheating within 15 minutes and you could feel the difference in grip, from leaving the pits to being 10 minutes, beyond this point the grip diminished considerably. while still grippy the entry speed into corners had to be reduced.
Running them at 28/30 the car seemed more stable after longer periods on track.

I'd be interested to hear from anyone who has played with pressures and found a good all round pressure grip/wear for R888's as this currently where i'm at.
The slicks will be going on the fronts soon so any info on them would help too, i beleive the compound is similar/identical to the michelins the cup racers used to run. R888's will be kept on rear as unlike many stories i've heard i feel the rear is pretty stable as is, and slight looseness at the rear (insert your own joke) will help with tight corners.

Chris

 

[asim]

I was once recommended by Mark Fish to keep them at 30 front and 28 rear for PE2s. I've stuck to that since for road use.

 

[ravydavygravy]

Just altered mine from 29/26 to 32/29 for the colder months. Bejeezuz i nearly got out of shape on a roundabout

So much more grip at 29/26 and less 'skittish'.

Thinking of dropping them back down. Will it have any adverse effects?

 

[Gazza]

Had new tyres fitted on the rear on Friday and had a slightly scary moment in a high speed bend. Just checked tyre pressures 32F 37R :shock: So much better now im running 32F 30R.

Tempted to swap the new rears for the 3/4 worn fronts, what do you guys think?

 

[Gordon]

Do it. Especially as winter is on the way. I'd always suggest you should have the most tread on the driven wheels in poor weather/surface conditions, especially on a front driver. Naturally less tread on the front (closer to slicks) could give better performance on dry roads in summer.

You can also give the fronts a good clean at the same time as you swap them and give them a rest from getting brake dust baked on to them.

 

[pete g]

George is basically right with his ballon but choice of fluid could be better as water is not compressible, thats how a flooded engine can bend a rod and steam engines have cyl drain cocks!

Small changes to TPs on road wont have much effect unless driving like a lune.
A lot of us run a bit softer to give some relief from the hard damping/ride, say 30/28.

For hills and tight short sprints you can go softer... a) for bit more traction and b) get more heat into tyres.

For fast track work start at std, pressure will come up as you work the tyre then adj at higher pressure say +4 but keep the front rear diff around 2/3psi.
If happy with balance of car thats fine, if you want to reduce the u/steer a bit more in the front is my choice.

Hope that helps...?

 

[PeterGinger]

I run 34F/30 Rear. I seem to be the only one. However, I have found that no matter what pressure I use on the front when on track, I just wear out the side walls. I do have -1.75 camber. Should I go massively softer, fit track tyres, or driver slower. I do love the fine steering feel you get with the higher pressures. Although I get more grip at slow speeds with lower pressures, they are just too wallowy when pushing it hard.