Just going to leave this here for you Tamiya spring users
2wd Front: 54507
Hard springs x2 (.61 spring rate) =3.48
Medium springs x2 (.56 spring rate) =3.19
Soft springs x2 (.52 spring rate) = 2.96
4wd Front:
54506
Hard springs x2 (.76 spring rate) =4.33
Medium springs x2 (.70 spring rate) =3.99
Soft springs x2 (.64 spring rate) =3.65
2/4wd Rear: 54508
Hard springs x2 (.43 spring rate) =2.45
Medium springs x2 (.40 spring rate) =2.28
Soft springs x2 (.37 spring rate) =2.11
Multiply the above by 5.71 to get your lbs. equivalent