To amplify the difficulty of attempting to be so precise, I run our Pack races on my own 35 ft BestTrack. My house is not level, I think the Gym floor is level- at least pinball test looked good. Anyway- without the Cubs seeing times I computer record them during testing at my house to help catch any serious problems.
Same track moved to a gym and I have never had the fastest car during testing win at the Pack, always some car that was 2nd or 3rd runs faster. Individual cars at the gym run much slower- 0.02 to 0.04 sec on good rail runners- way worse on random alignment.