tyre pressures on track - road tyres

[nicole_]

Was after a bit of advice, I know theres lots of threads and I've searched through most but was looking for some specific to me help

I'm off to Cadwell on Friday, it's sessioned into 20min on/40min off all day.
Ek9 is on Proxes 4 with 33 psi all round for everyday driving - sadly my RSRs wont be here in time (
Baring in mind its sessioned, and i'm on not the greatest road tyres..what would you recommend for starting pressure?
I was thinking of 28 front/30 rear..
I've got an hour drive before I get there too, so wont be completely from cold. On a previous sessioned day in a different car, I ran the factory recommend psi and didnt need to adjust this all day - it was wet though.

 

[kellsled]

When I was on track with my teg and running r888 I ran 25 cold and by time I had session done I was up to 30+ again I'd go 25 all round from cold see how u get on and adjust it to how u feel it

 

[Lee s]

I prefer edgy handling around cadwell, run 30 cold all round and it's great for me. But I use the rear a lot.

 

[jesse888]

30cold is wayyyyy too high even for semi slick your want to aim for that hot.
I did 1 trackday on t1rs once. Adjusted my pressures as I always do, 25 psi cold to start then adjust after first session. After just 15mins the front had gone from 25psi to close to 40psi! I had to adjust them afew times as the pressure just kept creeping up. Once I'd let them cool down they ended up 18psi iirc.
Depends how hard you drive I'd say start at 23cold the first session, then as soon as you come off adjust them back down to 28/30psi.

 

[ek9cub]

I run 25-26 psi cold on ad08's, I'd try 26 then just keep checking but like said 30psi warm is your aim.

 

[clockwoRk]

on road tyres i would aim to have standard road pressures when hot. maybe a pound or two lower .. you won't have the sidewall stiffness to run much lower like you would with list 1b tyres. basically it will make the car feel loose and vague and too low in the rear will just give a lack of feel so could have the back let go without much warning.

probably before going out on your first session i would drop 7 or 8psi from your front tyres and 4 or 5 from the rear and then check them as early as you can when you come in after your first session and adjust again to match road pressure. then keep repeating after each session, maybe drop an extra pound or two out if you're getting confident.

 

[tama666]

on road tyres i would aim to have standard road pressures when hot. maybe a pound or two lower .. you won't have the sidewall stiffness to run much lower like you would with list 1b tyres. basically it will make the car feel loose and vague and too low in the rear will just give a lack of feel so could have the back let go without much warning.

probably before going out on your first session i would drop 7 or 8psi from your front tyres and 4 or 5 from the rear and then check them as early as you can when you come in after your first session and adjust again to match road pressure. then keep repeating after each session, maybe drop an extra pound or two out if you're getting confident.

 

[kulo]

aim for 30 hot

 

[clockwoRk]

Thanks tamma. I typed all that on my crappy phone. Feel quite proud of myself to manage it with the keyboard taking up almost all of the screen and autocorrect trying to trip me up every other word.

 

[tama666]

Thanks tamma. I typed all that on my crappy phone. Feel quite proud of myself to manage it with the keyboard taking up almost all of the screen and autocorrect trying to trip me up every other word.

You did a great job man! as always.

 

[JohnTurbo]

I use 31psi hot. Its often tempting to underinflate semi slicks but they like a bit of ridgity. Once went to a trackday with a Toyo rep there and he was aving every one pump their tyres up based on pyrometer results.

For R888:-

VEHICLE WEIGHT COLD PRESSURE HOT PRESSURE
Very Light < 800kg 17 - 22 psi 22 - 29 psi
Light 800kg - 1000kg 20 - 26 psi 24 - 32 psi
Heavy 1000kg - 1400kg 23 - 27 psi 28 - 40 psi
Very Heavy > 1400kg 27 - 35 psi 37 - 40 psi

 

[Stakis]

with r888 or v70 try them at 28-30 hot. you can play alittle bit with front and rear pressures to control oversteer or understeer.