Track Day tyre pressure.

[Soot1e]

As above, what do you all recommend on a VRS with standard wheels and tyres, Toyo T1's at the moment, we'll assume its a dry day. Over the few track days I've done with various cars no rule like 10% harder or 15% harder seems to apply, but has more to do with the type of car I'm driving and whether FWD or RWD.

So any suggestions on my pessures are welcome.

[devonutopia]

I thought you had to drop pressures a bit as the heat built up during track use increases tyre pressures by quite a way?

[Soot1e]

Blimey that was a quick answer Jason. Reducing pressure I've never tried as I've never had a problem with overheating tyres, we are not exactly using F1 power and slicks.

[devonutopia]

No - I doubt very much I will bother at Hullavington. Sooner just drive up, drive on, thrash round, and drive home. Eventually the pressures should get back down to normal.

[faboka vrs]

I normally go for about 5psi more when hot. So like Jason says reducing pressure and they soon increase. I normally go out for a few laps then come in and reduce the psi makingsure it's even both sides. Then after each session keep monitoring the temps.

[ncarring]

Most people go for increased pressure. The reason behind this is the additional sideways force that develops when cornering hard, leading to more heat being generated in the tyre by sidewall flexing. Heat is one of the major contributors to tyre failure, hence the desire to minimise this flexing.

In some forms of motorsport - off-road mainly, trials for example, very low tyre pressures can help with traction on loose surfaces. I wouldn't use reduced tyre pressures on the track.

One indicator you can use is how far down the sidewall the scuffing comes when you've been out for a session. If it extends below the bottom of the tread pattern, you need more pressure.

[cheezemonkhai]

Doing a handling day they instructed us all to up the tyre pressures by about 5PSI as otherwise the flex in the sidewall would cause issues.

One of the attendees had the tyre come clean off the wheel on one side (and go back on properly too) and I would guess this was due to too much flex.

[yegnold]

Soot1e I will have a digital tyre pressure gauge and a crappy air compressor if you or anyone else needs to adjust the pressures on the 31st anyway

I will also have two spare wheels with legal tyres on that, if I don't need, I would be happy to lend to a fellow Briskodian if they buggered a wheel or tyre.. and will also be bringing a trolley jack, limited tools, engine oil and coolant if anyone needs them.. we'll be sorted.. I just need someone to look after all the stuff whilst I'm lapping

[devonutopia]

Up sounds more sensible. I sure scrubbed my sidewalls doing Llandow & Boovy a month ago. I did both just keeping stock pressures and not bothering to release any excess pressure built up due to heat.

I'm bringing 2 wheels as well, toolbox (on wheels it's that big ), mini compressor, gauge, oil, and some other random bits, Hopefully it will be a dry pit so no need to worry about rain damage. Ultimate thing would be to have a spare car there not going on track, to load up.

[yegnold]

Would need to be an octy or superb though,

[devonutopia]

Roomster

[Soot1e]

Sounds like we'll have a mobile garage on the day, all we need now is a four post lift, anyone? I'm bring my trusty footpump and pressure gauge.

Will try different pressure throughout the day and see how it goes.

At North Weald we were told to pump the tyres to 50psi to stop the tyre coming off the rim but it did seem a bit hard and not very compliant with the bumps.

[Soot1e]

One indicator you can use is how far down the sidewall the scuffing comes when you've been out for a session. If it extends below the bottom of the tread pattern, you need more pressure.

Good grief! I'll be cornering on 4 wheels not 2.

[ScoobyChris]

Very interesting thread

I've been recommended to put 3 or 4 extra psi in the tyres for track days and as Nick says, well worth tweaking them on the day to find a pressure that works.

One indicator you can use is how far down the sidewall the scuffing comes when you've been out for a session. If it extends below the bottom of the tread pattern, you need more pressure.

Sounds like I need to put some more air in my tyres .... or stop letting the hooligans drive it

Chris

[ncarring]

Good grief! I'll be cornering on 4 wheels not 2.

No need to be that extreme to benefit Magic shoe polish

[Soot1e]

Yanks! Don't they go over the top? White polish, I really can't be bothered.

[Jonny5ive]

Roomster

Alas, mrs Jonny5ive will not be in attendance :(

I might consider putting a spare wheel in for Hullavington :rubchin:

[PastyBoy]

i may have to make use of the mobile workshop to swap some wheels and sort tyre pressures on the day - as payment i'll see if work have an estate i can bring along to act as storage area for the day

[insanity]

For drag racing, it is better to use lower pressure?

It is better for the traction to have the tyres warm?

How can I gain the most effective "launch" without launch control? I'm going to a race on the airport sunday and I still have a lot of questions I tried a lot lately, but I still don't know which is the best way to start.

The best way I found so far is to have a steady 4000 rpm and declutch on green light but I'm getting a lot of smoke from the tyres and this means that I'm loosing precious time...

Can u help me please?

I have a beautiful Octy mk1 RS 225 bhp

Thanks

[oilburninnut]

i found the best way was to launch in 2nd,slightly down on the pressures,with tyres warm after doing a long burnout through the staging box with the handbrake on,have fun:thumbup:

[Jabbasport]

For trackdays stick a sheite load of pressure in the rear tires, call me mad, but try 50psi cold which might rise up to around 55psi...

:D

Kev

[PastyBoy]

For trackdays stick a sheite load of pressure in the rear tires, call me mad, but try 50psi cold which might rise up to around 55psi...

:D

Kev

I found almost completely bald tires and rain had a very similar oversteery effect

[darrenbedford]

i think youll find kev right on his quote, he races in the same series as me, go for about 28 front and 46 rear, as you get quicker up the rear a bit.

[mk4gtiturbo]

In my trackcar (mk2 Golf GTI 16v) I upped the pressures in the front.

Best thing to do is experiment. I had an open pitlane day at Castle Combe and learnt loads by changing the pressures each session.

Interestly enough I think we run the Caterham at about 17 psi on competition days.

[insanity]

in 2nd gear? isn't it to slow?

I'll try tommorrow