Greetings, it’s not shown on video, but have you considered putting your cars on equal footing before conducting time trials? Respectfully, a few recommendations… Track: 1) clean the track, use a lightly damp microfiber cloth to clean the surface. Allow any moisture to evaporate, then wipe it down with a dry microfiber cloth. Vacuum or blow out the slots. Cars: 1) remove the body, inspect the chassis for anything obvious that will interfere with performance. 2) clean the body and chassis as necessary of any dirt/debris (I use a small paint & toothbrush.) Pay particular attention to the areas around the gears, axles and bushings, look for and remove any debris in those areas. 3) lube the bushings where the axels pass through with a plastic safe oil, apply plastic safe grease on the gears. 4) check the wire braid on each car for wear and cleanliness, use a soft metal brush to groom the brushes as/if necessary. 5) true as best you can at least the rear tires and clean them (using masking tape) on each of your cars PRIOR to your 10-lap run. You may be surprised how a little maintenance/tinkering can positively affect the performance of your cars. Cheers.
I like your classification for tuning (Stage 1,2,3 etc) 😃, did the same to some Carrera Gt cars and goes something like Stage 1 only front and rear tires, Stage 2 add guide adapter and Slot it guide and spacers on front axle, Stage 3 add Slot it V12/4-21 motor, Stage 4 add front/rear alloy wheels and aluminum gears, Stage 5 would be a full 3dp chasis and all the extra stuff you may want to add(open class). Keep the good work mate and I look forward to watch your videos on the DISCA racing ! 👍🏼