HA OEMAHGAWD He got STP in his name!?!?!??!1?!/!?!1
Fuck, its old.
Unless you're prepaird to doa hell of a lot of digging its not worth it.
They all depend on how big the jump is. If the jump it like 5 foot high and has a 9 foot gap, and a 10-15 foot intersection between lander to next take off, it should be like 3 foot deep or so.
The Bigger the jump, bigger the gap, bigger distance from Lander to Next up ramp all make the pits different.
Just dont put pits befor the first jump, unless you make a roller to get into it or something.
Just try some out, dig it deeper or fill it in abit, just till you feel that its perfect.