Went up last night and got some serious practice down with the car on black carpet. Still running the stock Alloy chassis but have the braced front and rear arms on it.
Only 2 changes I made from the last practice was switching to Mugen 7.0 progressive fronts and Mugen 6.5 regular rear springs. Also put a 1.6mm top deck that Krazed Builds is testing.
Friday nights the track is dry low bite to start and usually not many people (if any) practicing so bite isnt great. Started the night practicing on 3 different sets of older USGT tires. They were flat and clean but with a dry track I knew it wasnt the greatest.

I'll run through what I tried and felt from it.
Rear toe @2.5* - tried 3mm shims under the ARS at the wheel (more is less). Car was over rotating and rear coming loose on exit. Went back to 2mm kit and rear stayed behind the car, added a click of steering all with no negative effects.

Rear shocks was trying to gain on power corner mid/exit steering. Mugen 6.5 hole 4 and 1mm shim behind lower mount ball stud. Felt too much steering - too much throttle on exit and rear was loose, on entry weight shifted forward to quick. Miss the line and had to feather the throttle to get back in line.
Dropped the rear shocks to hole 3 gave me on power exit push, caused me to delay getting back to throttle mid/exit in the corners. More forgiving though if I missed the lines but recoverable from lack of throttle.
Put the Mugen 6.25 on the rear and hole 3 had to add too much steering. Put it to hole 4 and felt a better balance mid/exit vs throttle. Front to back the car stayed flatter but still rolled giving me traction to roll the throttle on mid corner.

Upper arms was running 1.5mm shims to lower RC - felt like it was trying to drive the tires into the carpet for traction. Dropped back to kit 1mm and felt the car carried speed better through the corners. Didnt gain but rolled through the corners with no need to pull more throttle trying to save clock time.
Did make the car feel loose overall though on the older tires.

Dropped the lower arms from kit 1mm chassis shim to .5mm to lower the RC there. Felt traction in the tires come up with out loosing the freeness of rolling through the corners. Dont honestly understand the difference between upper and lower arm RC changes but felt doing it at the carbon arms/chassis was a better decision.

Motor mount screws - I was running the rear 3 but switched to the front 2 instead. Feel like this free'd up the rear to flex and gain traction with out loosing front flex. Felt close to the feel I got from the Center Flex chassis that Krazed designs. Drive train was free'r allowing the car to have a balanced flex front/rear.

Started the night able to run 8.1 occasionally and 8.3 range on average. After trying these changes felt the car able to run more in the low 8.1 range.
Knew it was time for some fresh tires and see how everything reacted. First run on new tires I could feel a bit more consistency, got a couple 8.0s and more consistent through a run.
Balance felt a little off with the on/off power weight shift so used my droop screws to adjust it a bit. Took a little out of the front to keep some on power weight forward and little out of the rear because I felt the nose was dropping to hard on entry/off power.

When I put new tires on I also adjusted the gearing a smidge. All night I felt the car was slightly over geared, not like drop a tooth over geared or motor was hot. I could feel the car just top out as I had to lift for entry. At times causing me to overshoot the corner. So looked at the gear chart and was running 42/102 = 4.42 ..... drop a tooth and Im at 4.52. So i wanted a bit around the middle. Changed my spur and pinion to 44/108 and gave me 4.46 overall. 1st battery on new tires I was topping out before I had to lift for entry and not over shooting infield corners. Adjusting timing is so sensitive and dropping pinion teeth can be too dramatic. Pinion and spur changes for me have the greatest benefit.

2nd run on the new tires I was in the 7.9/8.0 and car felt hungry. Cleaned the tires and checked everything on the setup station. Some wall whacks I had thrown things off a bit.
3rd run i had the car squared up again and tires cleaned and broken in well. Car was planted, could correct a line and grab throttle mid corner. Could purposley blow a line and recover it right back to a fast average lap time. Tying to simulate traffic and recovery.