rocket lift bar mounts

[lpd1]

i have seen some cars lately that are running really well that have drop mounts on the bottom of the rearend where the lift bar mounts which lets you lower the lift bar? my question is why? do you gain anything from lowering the lift bar down? or is it so they can run a j-bar pinion mount lower which in the end gives them more rake in the j-bar? which you can do by raiseing it on the chassis? thanks for your veiws i notice alot of pittsburg cars and other super slick track doing this.

[C10]

We dropped ours because we couldnt get to the bottom hole with out shorter J bar. The heim hit the lower tube of the lift arm