First track day, where to set tire pressure to begin with?
 

Got my first track day lined up this weekend. Running stock car with stock wheels on mostly all season 205F/245R street tires. Temps should be around 55 in AM and 70 in PM. Coarse track surface but short. May touch 100mph briefly on the straights.

Where should I set the tire pressure to start with? Factory settings or higher?

I've done years of autocrossing in a Miata so I'm familiar with marking the sidewalls and reading the rollover patterns. The 911 is a new beast to me though.

Just looking for a starting point before I go thrash them.

Look up your tire on the web. They may have advice for you. It would also be useful to know what tires these are.

I'm sure you'll get lots of opinions, but my two cents would be the factory recommended pressure +2/-0 psi.

With the expected temperature differences you're going to have to change the pressure anyway. You may be skating in the morning and yet feel fine once the day warms up. Set it where you think and then see how it all feels and adjust as needed. Bring a pump or a compressor but focus on the driving first and foremost.

I would set at the manufacturers suggestion, leave it there, forget about it and do not think about making any adjustments at all.

If this is your first track day - reality is that you are very unlikely to have the driving experience or skills yet to be able to tell the difference that slight changes in tire pressure are going to yield. Thinking about things like tire pressure at that stage of the learning curve is putting focus where it is not needed.

Focus on the line and what your instructor is telling you. Focus on being smooth. Work on keeping your eyes further down the track. Try to pay attention to weight transfer and keeping it super smooth under braking and cornering. Work on smooth shifts that do not induce weight transfer. All of these are fundamentals to building up to going fast.

Until you get to the point where your driving the car at its limit (and not yours) and your laps times are consistent (within 2 seconds of each other barring traffic) - don't bother with things like tire pressure.


Terry

I've done a few track days and years of autocrossing so I got a few skills (and I do mean only a few). ;)

The 911 is new to me so I wasn't planning on messing with the pressures much. Just wanted to know if I should increase from street pressures as is normal practice for autocrossing or just leave alone and watch the sidewall roll.

I really want to gain a feel for the car and backend handling characteristics before I really start pushing it hard and getting it really dialed in. Something tells me this will be a whole different experience than my Miata.

I would suggest setting them 2PSI below factory settings to begin with. I would check the back tires throughout the day to keep them around 38 degrees hot. Adjust the fronts to keep the stagger the same if you are happy with it. Unless you are a hardcore racer, I think this gets you pretty close. This is what I do on street tires, assuming your not running slicks. Have fun, its a blast.

Are you running at little Talladega?

Yup, Little Talladega on Saturday.

I was there a few weeks ago but I am running R compound so no help. Have fun. What group are you going with?

if you are running street tires, you need to set them at @ 5-7 lbs OVER, not under. Try 37-38 in the front and 39-40 in the rear and you should be fine.

Erik, how did the greenie meanie run on the track????

Set them at about 3-5 psi higher than street and drive. If they get greasy, reduce pressure in 2-3 psi increments.

Most important, listen to the instructor and have fun. You will find your AX skills will help you in some critical skills sucoh as looking ahead, placing the car were you want and maintaining your line.

Tell us how it went.

congratulations, you are about to step on the dark side. as you will most likely be told this weekend many times, "welcome to your new addiction".
as far as tire settings is concerned, I'm suggesting to start whatever is posted on the sticker in the door jam + a few and then as the day progresses, back off or add some psi based on how the car feels to you.
one thing that I did years ago is created a journal to make notes, so after every session I check my car's tire pressure and write it down along with any other notes about that particular session. maybe something along the lines of how I handle a particular traffic situation, or experimenting with a different entry/exit in a corner that I'm trying to get faster at. anything really that I can go back to and review especially at the beginning of the season or if it is a track that I haven't driven for a long time.
just experiment with what you feel most comfortable with and what works for you. part of the fun to me is the trial/success with different things or a combination of things. good luck this weekend.

Just to be clear guys are you talking about hot or cold pressures? i am assuming hot?

Marc - the green meanie was awesome, I have couple of questions I need to ask you about brake performance - I will shoot you an e-mail.