Sprint tyre pressures

[harrison140]

I wondered if anyone with more experience than me has some information. I am doing a sprint at Lydden Hill in Kent in July I've done a lot of track days there and I set my pressures to 20psi cold and that seems to be about right. The sprint is 1.75 miles long I think even though it's a short course the standard road pressures with be to high any ideas ? I'm using AR1 tyres.

[G1en]

20psi seems too low if its a 350/370 your driving. I have never gone that low but that doesn’t mean i’m right your wrong. Just try a few combinations and see how the car feels, ultimately its what works for you, i have had no end of people tell me what pressures to run on the 350 at sprints/hillclimbs, they didn't work and do my own bum cheek testing now.

I know the AR1s have a relatively stiff sidewall so you can get away with lower pressures but i would be very surprised if your didnt feel better turn in and sharper steering with pressure up near 30 at the front. I run usually 5psi less at rear for traction and due to car being lighter at the rear.

From my experience the pressures only go up 1 or 2 psi on a sprint run where as on a track day they may well go up 10psi over numerous laps if pushing.

I would try 30 front 25 rear and see how that feels, just for comparison my last sprint day with the 350 i was running 34 front 27 rear with yoko AD09. Last year with A052 it was 34 front 31 rear. I have run Ar1s in past but was 5 years ago so cant remember what pressures were but certainly no where as low as 20, dont think i have ever gone below 25 on any tyre, maybe should try it lol.

[harrison140]

Thanks very much for the info I have used AO 52 in the past better tyres but I couldn't get any last October the AR1 is ok as long as it is dry. I will go with what you suggest and see how it goes