I had my first track day:
[ame="http://www.youtube.com/watch?v=m9qqv2lZb-o"]ST XTA coilovers for the GT86/FR-S/BRZ - track day[/ame]
I can now say for sure the 6 kg/mm front, 5 kg/mm rear springs are not an issue. I this the 2 axles should be viewed more independently.
The front is very planted and is very roll resistant with the higher spring rate. It has a firm grip in the corners and I didn't remember having understeer at any point at all! The stock understeer at speed is completely gone as well. As an example, I come into the first 3rd gear lefthand curve (Earste) slight fast at approx. 10:55 into the video and have to counter steer a bit.
The softer rear has very good traction and but is still slightly tail happy. It actually caught me by surprise on the very first lap, that it was possible to get the tail to step out in 2nd gear by applying power.
With this setup I would say the car is neutral biased towards oversteer.
Next up:
- I really need an oil cooler. Oil temperature was around 130 C degs / 265 F.
- I really need to change to Castrol SRF brake fluid, the brakes got mushy after 4-5 laps.
- I really need proper track tires.