on the stunt tracks there are wooden ramps on some tracks leading to short cuts unfortunatly theas shortcuts are mined if you make it thrue you can make some time but your allmost garanteed to hit a bom and its all a waste att worst lose time but if you use the ramps but then drive off to the right to the normal course its like a boost and no bom crates it can be helpfull as the areas before the ramps can often slow you dow especialy if you make a small mistake
its somthing im still working on but worth a try :)