If your running a RB WS7, I highly recommend running a RB,NR,Top, or REX 086 pipe, or 053 pipe. You are running a high end motor and it deserves a high end pipe. Those motors are not tuned for low end, because all the tracks in europe call for top end with not many jumps, therefor low-end torque is not something they need. If you want to get some bottom you must tune your clutch. You didnt post what kind of car you have or what clutch you are running. I recommend running the 1.1 springs, aluminum shoes, and maybe even drill a small 1/16 hole in the shoes to lighten them alittle for a later engagement. If your using carbon shoes do the same. This has been a good set-up for RB users.