Just wanted to create a thread to discuss tire pressures as people seem to be all over the place and I can't imagine the there isn't a sweet spot.
Those are close to what works for me, hot. I aim to keep the front closer to 34 for road courses. Keep in mind that I'm running nearly -3 degrees of camber up front. If you can swing it, you gain good mechanical grip at lower pressures.Fastest times for me have been at 36/32
Yesterday, I had my best run at 40f/40r on a small tight course. (Sport mode)205/50-16
For my driving style, the pressures best for me are 40F/38R. I may bump the rears to 40 to see if I get more response for the smaller/tighter auto-x courses. So far, I have had better results in Sport mode and not OFF, but I am coming from an AWD WRX, so I'm still learning what I can and not do with FWD. My settings may change over time.
Lower than those and I roll onto the indicators. Much more than that and I don't get out to the edges
Ran 36 front and 34 ish rear yesterday in the rain with 40 degree temps. The car didn't push and it rotated very well. When it dried a bit the car was full of grip and was lifting the inside tire constantly. I myself only drove it in a downpour but it still had plenty of grip in the cold/wet.
This is pretty much where I ended up as well. I usually start at 55 in the rear and have gone as high as 60 to encourage rotation. The 39-41 range on the front depends on grip levels and clockwise/counter-clockwise orientation of the course. The predominately outside front tire goes 40-41, with the inside at 39-40. Lower than that starts to create too much rollover, and too much more creates more wheelspin.Where I have settled after about 5-6 events in the FiST.
Fronts 225/45/16 ZII - 39-41 psi
Rears Stock tires - 55-58 psi