Steve sets up a table and has supplies for dads (or in some cases, grandpas) to use to make their kids' car compliant with the rules. He has a drill and BBs, so you can make the car lighter or heavier as needed...and also lots of graphite powder. It was amazing to see guys still working on their cars, right up to the end.
It's been a while since M did pinewood with the Scouts. But IIRC, it was much more cut-throat than this. This is very laid-back. Lots of laughing and kidding around.
One elderly man brought his grandson and was put out because he thought his grandson's car (which was bulky) shouldn't be racing against smaller cars...it should be seperate, or something. He didn't seem to realize that the kid decides how big the car is going to be. Grandpa wasn't happy, but that was the only stress there was, and it wasn't much.
You don't have a strict weight limit?