I have 2 of these.
1 is in my truggy and i run it with an OS 2060 pipe. everyone always said to me that it wouldn't have enough power for a truggy but i think its insane. the WS7 revs out so hard that nothing can catch it.
My second one is in my buggy and its even more insane in the buggy. I also use an OS 2060 pipe in the buggy. I have never tried the RB 2045 pipe but with the power and run times i get with the OS pipe i not going to bother.
Just be sure to give these motors a good run in. i use the heat cycle method and then keep them a little rich for the first few liters. they do take a good gallon to completely wake up and when they do you'll never buy another brand motor again