In order to unlock the Leap of Faith Trophy you need to perform 8 different jumps over 100 meters. As per the game you should complete 16 jumps over 100 meters but there is so glitch with the registration of the jumps so you can only perform any 8 jumps and the trophy is unlocked. You cannot measure the distance on how long the jump was, but you can use the waypoint for the reference.
There are a lot of ramps where you can perform and if you have trouble with one just move to the next one. As we mentioned earlier you only need to perform 8 jumps over 100 meters so you can select any 8 from the below locations. We recommend to put the marker at 100 meters on the map from the ramp by driving slowly first and the second attempt should be your perfect jump covering 100 meters.
Sometimes you need to try multiple times as there is a glitch that does not register the jump or you fall few meters short. If the trophy doesn't unlock after 8th jump then continue further as it will unlock in with other jumps.
Below are the Locations of the all 17 ramps to unlock the Leap of Faith trophy.
Hope this guide was helpful and you have unlocked your Leap of Faith Achievement. :)