Ran the roll center mod on carpet with foams today. Car felt very good, but did not have enough turn in with 6 degrees of castor. I went to 8.5 and the turn was good. Overall the change was good and the car felt more consistent and less erratic. I tried kick up and pro-squat. I liked it best even, but prosquat felt better than kick up.
Also tried Associted #3 pistons with 80 weight in the front and the car had a bad chatter. #2's with 80 all around feels best thus far.
Experimented with upper arm location on hub. Short links seem to let me carry the most corner speed. Long links feel good and are stable, but I feel a loss in the infield.
With really small tires (2.20 or less) I had to go to a softer spring in the rear for traction. Car seemed to lose traction about 3 minutes in.
I was able to get a 128 (64 pitch) spur gear on the car with the adapter and the car had excellent acceleration and straight away. I tired stock and mod and it was awesome. Bigger the spur the better with 20t pulley.....
I am going to try putting the front back down stock and lowering the rear arms to be equal with the front and see what effect I get there. Reversing the current roll center mod. Lower the rear instead of raising the front...... Might be awesome. Might not
Hope this helps!