Tire Pressures
#1
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I've been researching the Forum back to 99 re tire pressures and I admit to getting confused, I'm putting the car on a track for the first time - training course so I'm hoping someone can put me straight.
I have 18 inch wheels with 225/40 front and the optional 285/30 rear, according to the book the pressure should be 36/44 for day to day use. I understand the 285 will increase the grip hence it's possible to drop the differential front/rear a bit to gain better balance, ie the fronts will tend to understeer more say so try 36/42?
But generally for track work you raise pressures, whereas a lot of forum people - know doubt experienced recommend dropping the pressure some say to 32/36 cold assuming a rise to 38+/40+ when hot.
Help!
I have 18 inch wheels with 225/40 front and the optional 285/30 rear, according to the book the pressure should be 36/44 for day to day use. I understand the 285 will increase the grip hence it's possible to drop the differential front/rear a bit to gain better balance, ie the fronts will tend to understeer more say so try 36/42?
But generally for track work you raise pressures, whereas a lot of forum people - know doubt experienced recommend dropping the pressure some say to 32/36 cold assuming a rise to 38+/40+ when hot.
Help!
#2
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Your own driving technique (or lack thereof) is the greatest variable. From whatever starting point, the pressures will rise. The amount of rise will depend on how hard you push, and which end you cause to generate the most heat. Typically, the rears will rise most. If you are just starting out, you could drop the pressure by 3-5 pounds per tire, and check the pressures when you come in. Keep bleeding the tires to keep the hot pressures below 36/44. The ambient and track temps, the number of laps, and the vigor of your driving are unknown variables. AS
#3
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Also, you did not mention the brand of tires, "R" or street, etc. Simply put the advise to start out with is good from Specialist. After coming off the track, perhaps in the track out section, or immediately in the paddock area, take the tire pressures and note them. If you can check them with a pyrometer, better yet to record the heat on the surfaces of the tires; one side, middle, the other side. Also, as was said, your "feel" during the session, such as oversteer, understeer, noise, wear and tear, etc. over time will enable you to adjust over all tire pressures...as well as fore and aft.