Spent another day testing and zeroing in on my XRAY X4s overall rollcenter balance first.

As noted in my last test report I felt that 1.5/1.5/2.0/2.0 lower rollcenter would be a good base for low grip and that promised to be true.

What really helped get the tires into their operational window was raising the outter camberlinks. I ran 3mm on the hubs at some point, but since the lower rollcenter shim on the hub is 0.5 front and 1.0 rear, I ended up with 3mm front on top and 2.5mm in the rear. This way the overall height is the same and only the axle height is different. Gave a really good balance throughout the turn and a good overall roll behaviour.

I improved my fastest laptime by 2/10 from 17.3 to a 17.1 with the average lap also improving by a similar margin.

This time I did the fastest lap with a twister speciale (very far forward). It provided the predictable handling necessary to convert the knives edge performance of the first few laps into a meaningful average pace advantage, while from run 3 on the panthera privided a littel more steering to get more from used tires.

I have ordered a regular Twister as this is supposed to have a bit more steering to finally make a bodyshell decision (and sent both a Panthera and a Twister to the fantastic Apaint because I wouldn't yet bet on any one of them to be my weapon of choise in Apeldoorn yet).

Additional + factors for my performance improvement week-over-week:
- 2.8 rear spring helped with stability especially in early morning 'green conditions' with fewer people testing this time around, so grip level was lower.
- rollcenter balance as mentioned above
- 3.5 rear toe-link spacers to go with the lower rollcenter (gives 0.25 deg of toe gain under full compression, change along lower rollcenter shims - higher = higher, lower = lower, so that angle stays the same )
- change the brake rate value to 17 and the max brake epa on the radio to 90, because this gave the most consistent 5min brake feel
- twister wing on speciale body
- 8.0mm steering spacer (gives just over 25 deg of steering lock (despite the fact that I never really use full lock)

things that weren't better:
- heaters over 70 deg made the first 3 laps iffy without benefits later in the run
- a 1.3 rear swaybar took away steering without improving on-power stability too much

Ideas for tomorrow:
- deciding on bodyshells
- PSS (2, 4, none?)
- different shock-oil front and rear
- weight balance f/r
- fine tune flex
- keeping the racing line neat and tid

I am not fully satisfied and my personal motivation dictates that I shall keep on working, so I will go to test again all by myself this weekend which means I only have to plan around my own motivation and limitations:)