Road course tire presuure
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Instructor
Joined: Sep 2017
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Road course tire presuure
Putting on some new Michelin Pilot Sport Cup 2 tires on for road course. Can I get an opinion on cold tire pressure start? Going to Barber Motorsports in Birmingham next week. Cammed & bolt on mods. performance rotors and pads on vehicle. Done several road course events but not with this new tire brand.
Navigator
Joined: Nov 2013
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From: vancouver wa.
pilot sport cup 2s
Putting on some new Michelin Pilot Sport Cup 2 tires on for road course. Can I get an opinion on cold tire pressure start? Going to Barber Motorsports in Birmingham next week. Cammed & bolt on mods. performance rotors and pads on vehicle. Done several road course events but not with this new tire brand.
Melting Slicks
Joined: Jun 2005
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From: Rochester NY
2018 C6 of Year Finalist
St. Jude Donor '10, '17
There is no "Pilot Sport Cup 4", so I have no idea what the above poster is talking about. Additionally, you would typically not add tire pressure when going on a road course. Even with nitrogen, you will be heating the tires up and over-pressurizing (over-heating) them.
You are ultimately targeting a "hot" pressure, and how hot they get will depend on the road course you are on, your alignment, weight, ambient conditions, track surface, how you drive and a few other factors.
Most guys are targeting between 32-35psi HOT on Cup2s. Much more than that and the tires will overheat and lose grip. You should likely start at 26-28psi COLD and see where you end up after you get off the track. You will need to then add or take out air depending on final hot psi and most importantly how the car feels. So you need to check psi or temp after each run and make adjustments based on what you find, the conditions and how the tires are performing.
Here is what Michelin says:
Inflate the MICHELIN Pilot Sport Cup2 with a pressure between 1.7 bar (24 psi) and 1.8 bar (26 psi) front & rear
• Never allow the pressure to be below 1.5 bar (22 psi)
Hot tires
• The optimal operating pressure of the MICHELIN Pilot Sport Cup2 must be between 2.3 bar (33 psi) and 2.5 bar (36 psi) Front & Rear
• Never allow the tyres to run below 2,0 bar (29 psi) HOT
You are ultimately targeting a "hot" pressure, and how hot they get will depend on the road course you are on, your alignment, weight, ambient conditions, track surface, how you drive and a few other factors.
Most guys are targeting between 32-35psi HOT on Cup2s. Much more than that and the tires will overheat and lose grip. You should likely start at 26-28psi COLD and see where you end up after you get off the track. You will need to then add or take out air depending on final hot psi and most importantly how the car feels. So you need to check psi or temp after each run and make adjustments based on what you find, the conditions and how the tires are performing.
Here is what Michelin says:
Inflate the MICHELIN Pilot Sport Cup2 with a pressure between 1.7 bar (24 psi) and 1.8 bar (26 psi) front & rear
• Never allow the pressure to be below 1.5 bar (22 psi)
Hot tires
• The optimal operating pressure of the MICHELIN Pilot Sport Cup2 must be between 2.3 bar (33 psi) and 2.5 bar (36 psi) Front & Rear
• Never allow the tyres to run below 2,0 bar (29 psi) HOT
Safety Car
Joined: Jun 2017
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From: North Georgia, USA
I'd recommend starting around 26 or 27 psi cold.
As @Mordeth mentioned, your goal is somewhere close to 34psi when hot.
If you get more than 7 to 8psi of gain, you would be better to first try adding a half pound to a pound of air. Sometimes excessive gain means you started too low, and the tire runs over optimum temperature and gains more pressure than you expect. If that happens, adding a little air will reduce the pressure at the end of the next session.
As @Mordeth mentioned, your goal is somewhere close to 34psi when hot.
If you get more than 7 to 8psi of gain, you would be better to first try adding a half pound to a pound of air. Sometimes excessive gain means you started too low, and the tire runs over optimum temperature and gains more pressure than you expect. If that happens, adding a little air will reduce the pressure at the end of the next session.
Last edited by C6_Racer_X; Oct 13, 2017 at 10:00 AM.
Supporting Vendor
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Putting on some new Michelin Pilot Sport Cup 2 tires on for road course. Can I get an opinion on cold tire pressure start? Going to Barber Motorsports in Birmingham next week. Cammed & bolt on mods. performance rotors and pads on vehicle. Done several road course events but not with this new tire brand.
Burning Brakes
Joined: Jan 2010
Posts: 792
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From: Dallas Texas
There's also a ton of helpful info and people in the Road-Racing section here: https://www.corvetteforum.com/forums...roadracing-23/
