It seems that you are basically
looking to investigate the friction between various road type surfaces.
If you want to look
at the problem without friction of the engine why not try the following:
(a) run the car onto
the surface in an unpowered state and measure the distance it takes to stop (for a given
initial velocity). Remember that the kinetic energy before braking is equal to the work done
against the frictional force (apparently the coefficient of friction between cars tyres and
asphalt is 0.72, car tyres and ice 0.15, car tyres and cement 0.9, car tyres and wet asphalt
0.45-0.70) and that between car tyres and grass 0.35).
(b) run the car down a ramp onto
the surface (again unpowered) and measure as before. Use a light gate to find the speed of
the car just before the braking process begins
(c) take a tyre off the car and roll it across
the surface (keep it upright)
(d) take a tyre off the car and slide it across the surface
(e) try loading the car with different masses to see what effects this has.
There
is a lot about the Physics of car accidents on the internet. The authorities
are especially interested in this in the USA and Canada.