The higher end 1/32 cars have set screw aluminum hubs on 3/32" axles so they can be trued on a truing machine. I have an old JK truer. Most 1/32 slot cars including Carrera have press on plastic hubs that are best left on the axle as they come. There is a truer called the tire razor that accepts the entire rear or front axle assembly and trues the wheels in place.
I have considerable success truing first the plastic hubs and then the hub and tire assembly on my test block with a sandpaper surface while connected to a power supply. It must be done carefully and slowly to prevent over heating the car's motor. These cars are considerably slower than 1/24th cars that run on commercial tracks and don't require the same high degree of precision. I trued my 1/24th Carrera wheels using my test block with the sandpaper surface.
Up till five years ago all my slot car racing was conducted with 1/24th cars on commercial tracks of 100' or longer. Average lap times were in the 4 to 5 second range. My 1/32 track is now 55' in length on a 16' long table. Lap times are in the 5 to 6 second range and I get the same feel as when I was racing flexis with hawk motors or FCRs with Parma 16D or super 16Ds. I have a few 1/32 cars with motors rated as high as 28K and they are a challenge to handle plus the spin their wheels all the way down the straights. I am by no means a "scale speed" freak so I keep the power turned up enough to make sure driving these 1/32 cars provides a challenge to the driver's skills. The impression of speed is more related the length of the track and to lap times than actual velocity. On a 150' track these cars seem to creep around the track.
Some people who have always raced 1/24th scale wing cars will not like making the transition to the slower 1/32 cars. But the advantage to me is that the track is in my house and I can go out there and run any time of the day or night and not worry about when the owner is going to have to close up shop. Almost every commercial raceway I raced at has either moved to a different location or closed up shop for ever. Also almost every commercial track I have raced on has gone through multiple owners and locations. I just got tired of chasing them all around the country side.
My track will be here until I die and hopefully after that someone will keep it going at their home.