If you're accelerating, and then press both W and S (forward and backward) at the same time, the wheels will visibly not spin, but you will still be going forward some more.

And doing this in a ramp or ledge, will cause the car to not fly and spend seconds slowly in air.

if there space after the ramp or ledge the car will just drop instead, potentially saving time.

Here's one time you can see me doing it in a ramp: