What sort of track are you running it on? If on wood you would probably benefit from weight near the rear wheels. Otherwise it is probably down to replacing the motor with something more powerful, such as Slot.it or Scaleauto or the tyres with something more grippy. I've got one of these that bizarrely ran very well without modification on a wooden track, and despite being Fly had grippy rear tyres.
A forum community dedicated to slot car owners and enthusiasts. Come join the discussion about collections, racing, displays, models, track layouts, styles, reviews, accessories, classifieds, and more!