If you will be racing in a Royal Ranger Pinewood Derby, or will be using a pinewood derby kit from S&W crafts, then you will likely be interested in the article posted at: http://www.maximum-velocity.com/royal_ranger_pinewood.htm The article provides some good information on wheel alignment for kits which use the 'dowel and screw' axle system. Best regards, Randy info@maximum-velocity.com