I Good materials for creating friction?

i was looking at the table of coefficient of friction and found aluminium on aluminium have quite a good range -up to 1.35.
what will be final spped at the tracks in the event?

 

Is friction what you want here? It sounds like you want softer cushions.

 

I doubt a 55g model car will have much in the way of controls, so I assume they are looking for something outside the car itself to stop it. Otherwise I would suggest a parachute.

I have an idea. Maybe make a sandwich with two carpets, and stuff some cotton balls between them to trap the car. See the attached picture.

 

Net and bungee cords .

 

I think a net will be too harsh an impact at 55mph, but perhaps put one at the end, after traversing some cushioning.

 

How about an arrester hook, and a spring loaded "trap wire/ cord"? Sort of the upside down configuration of a carrier landing..

 

A sand pit makes a good trap for the tractor-trailers that lose their brakes coming down a mountain.

If that's a little too harsh for you how about sprinkling some corn flakes or oatmeal on the track. (Also feeds the birds after the race) Peanut butter could also work but would be a hassle to clean up.

 

A wall/pit of bubble wrap? - the stuff used to package delicate items for transport.

 

Sponges might work.... Or sandpaper.

 

Why not an inflatable inner from a gutted sport ball...air bag effect.

 

The reason I suggested putting carpets above and below the car is to avoid a fast frontal impact. The cotton balls were chosen because they are much lighter than 55g so the car will push them rather than slam into them.

 

A pool of Uranium hexafluoride [gas]?

 

Use a glue strip under the wheels at the end of the race.

 

Some crumpled up newspaper.
Popcorn.
Partially inflated trash bag.