I recently aquired one of these cars through a trade, but upon looking at it decided there wasn't enough rubber under it for me, so I removed those skinny tires and wheels along with the axles and all the stoppers, bushings, etc... I replaced them with Sloting Plus America wheels 8.5 X 17mm front, and 10 X 17mm on the rear, Slot It. front tires , Paul Gage urethane rears, Slot It. axles, and Slick 7 bushings front and rear. Did a slight thinning of the rear arches to clear new tires. The pulleys were reworked also to gain space.