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View Full Version : TRACK & HILLS TYRE PRESSURES for grip



AIROCOBRA
21st May 2010, 02:41 PM
While I am researching tyres , here is a new question ?

What do you guys run your tyres at on the track ????

- brand of tyre & size ?
- slick or semi slick ?
- trye pressures for grip

Regards Bob

AJPS
21st May 2010, 03:45 PM
toyo r1r 195/50
street/light track
28psi cold for hills work

Pidgey
21st May 2010, 04:51 PM
I always used to run 32psi as a rule. But a professional driver ( has done over 3 million K's, trains special forces, races at lakeside etc, knows his shit) told me to run upwards of 40, as 32 allows the tyre to arch on the road, so that only either side is getting traction, not the middle. I tried 42psi, felt a shit load better. Was pretty shocked actually. Same guy told me that tyre companies tell you to run 28-32 because they'd sell more tyres than if you ran correct pressure.
Just as an experiment try 40, see if it's better.

marvis
21st May 2010, 05:14 PM
toyo r1r 195/50
street/light track
28psi cold for hills work
This. With 185 60 14 RE001

ke70dave
21st May 2010, 05:20 PM
toyo r1r 195/50
street/light track
28psi cold for hills work

really 28psi?
that seems rather low.

i usually go 35ish.
with kumho ku31? (one before the semi slick)

Pidgey
21st May 2010, 05:30 PM
^^ Pressure will raise with heat. Although it is low. Your pressure is pretty good though.

AIROCOBRA
21st May 2010, 05:35 PM
Hi pigeonspec ,
Higher did not work for me !!!! last hillclimb . I normally run 28 psi like AGPS , seems to grip well . But last climb forgot tyre gauge and borrowed one . I'm a wee bit on the blind side without reading spec's and the borrowed gauge had KPA / PSI reverse to my usual gauge . Bugger !!!! therefore was running about 46+ PSI .I am not normally into drift but I was on that day , bloody thing was sideways everywhere , ran out of lock couple of times , had one big spin . Had new engine with more GRUNT , but my times where shit .Spectators seem to be like it though .
When I got home was looking at the tyre guage ( spec's on ) . SHIT !!!!!!!! I run FEDERALS RSR 595 195/50/15 . There OK ? , Looking for more grip with next set .
Regards BOB

Pidgey
21st May 2010, 05:41 PM
^^ Each to their own I guess. 46 cold? I agree that would be too high.

AJPS
21st May 2010, 06:30 PM
I always used to run 32psi as a rule. But a professional driver ( has done over 3 million K's, trains special forces, races at lakeside etc, knows his shit) told me to run upwards of 40, as 32 allows the tyre to arch on the road, so that only either side is getting traction, not the middle. I tried 42psi, felt a shit load better. Was pretty shocked actually. Same guy told me that tyre companies tell you to run 28-32 because they'd sell more tyres than if you ran correct pressure.
Just as an experiment try 40, see if it's better.

I honeslty reckon it depends on the tyre

R1R have steel in the sidewalls, so theyre not sloppy and i get them pretty hot, so would raise from 28 obviously....

My car is light so i see no reason to run more

And yeah, 40psi is slippery.

biggo
21st May 2010, 10:28 PM
Front 30psi
Rear 40psi

usually works well for me as it cuts good skids when needed but not too bad when you have no low down torques

Konakid
21st May 2010, 10:56 PM
re001's 36 hot front, 38 once they wear a bit

sun_moon
21st May 2010, 11:01 PM
i run 38 to 39 in my mr2

Evocom
21st May 2010, 11:21 PM
Front- proxes 4s 32psi cold
Rear- Kenda Kr09 35psi cold which ends up around 42 when hot.
I started running the rears at 32psi which ended up just under 40 when hot and found there was much more grip with only a slight variation in pressure. All of the temps have been taken at the track drifting. I imagine the desired presure will depend on how you want the car to behave, your power level and handling setup etc. A case of trial and error I spose.

AIROCOBRA
22nd May 2010, 12:41 AM
I do most hill climbs in Canberra so getting heat into the tyres even after a good burn out before the start is difficult --- Canberra being colder that a yeti's bum in winter and with 1st car away a 9am , all the fast runs are in the afternoon if the sun comes out. Might see if any of the die hard drivers have one of those tyre temp things . It would be interesting to see a before and after result , but with even a real slow run you are still on the track for only 50 odd seconds . I think that 28 to 30PSI is a good place to start.

That reminds me last NOVEMBER went to the track at Marulan NSW . ran 30psi in the federals , each session was 15 minutes and for around 13 of those minutes had great grip but then for the last couple of laps the car was very tail happy . When I returned to the pits I remember tyres where very hot to touch . Should have taken a pressure reading!!!

Group A
1st June 2010, 02:42 PM
If you're running street tyres, try 36-40 psi cold.

Try 24-28 psi cold in R tyres. (semi slicks)

stouty
2nd June 2010, 03:44 PM
I run R888 in toyota T-18 853kg i run 28f 26r for for hill climbs and 26f 25r for super sprints they work there best around 30psi i have found. So find out what temp to have them so they will reach 30psi when warm.

4.5AG
2nd June 2010, 04:58 PM
Best Lap times on the racetrack was on 26-28 PSi cold.
According to yokohama website 33-36 hot was the ideal operating window.