I ran mini lipo's in my F104 tonight. We run 21.5 with no boost speed controls. Rubber tires on an indoor ozite carpet track.
Before the first qualifier I added 1oz of weight to the rear of the car. Better than no weight but still fought the car for the entire 6 minutes. Rear end was very loose.
2nd qualifer I kept it as is and the car was terrible as the traction came up. Others were traction rolling. I thought I was driving on ice.
Added 1oz more in the rear before the mains. That made a huge difference. I could actually pull the trigger