Tire pressures on track - Falken RT615K+
 

Headin out to the track this weekend and wanted to know if people running these tires have any thoughts on what kind of cold pressures the Falken RT615K+ like on the road course. I dont have a pyrometer so never an idea of what mine have been getting up to...

Thanks.

I would ask who ever is instructing.

Personally I would start at 28 cold. After the first session you should be around 38-40s adjust accordingly

I run 255/40-17 Falkens on my STX prepped BRZ, they seem to be happy in the low to mid 30's hot. I usually start with cold pressures of about 28psi (I run the fronts 1-2psi higher than the rears). Later sessions the tires usually start to retain some heat and they don't gain quite as much pressure.

I check the pressures in the pits and make sure they're even side to side (usually tracks favor one side or the other). The Falkens seem to be relatively forgiving with pressures though, you have to get them under 25psi or close to 40psi before they really start to get unhappy.

If they aren't making noise, you aren't driving them hard enough. When you get to the limit, they sing.

I really like them for track tires, they're 1-2s slower than an RE71 but they feel good and last.

With my particular setup, I start at ~30psi cold and after a 20 minute session I'm at ~36psi and 145-150 degrees F across the entire face of the tread. I'm not getting the temp at the optimum time though, as it's probably 5 minutes between the last run and by the time I get my car back to my pit area and take the temp with an infrared pyrometer, which itself is only taking surface temps. It's more important to be consistent in your methodology for comparison's sake. I run 225/50-16, so they seem to like a little more pressure than a lower profile tire would.. I've tried dropping them a bit, hot, from 36psi, but the only noticable change was feedback (less).
Keep them singing all the time, not howling.

When I had my RT615s I usually set them to about 35PSI hot and go from there depending on how the car is on the track.

As for what temps cold, you will need a bit of hands on learning to figure that out. Usually I do 30PSI cold and adjust down from there, but as you get more aggressive with driving you'll find you need to start off at lower temps.

-alex

Without using a pyrometer you are just guessing. Starting at 28psi cold might get you in the ball park but ultimately you need a pyrometer to determine the right setting.