I am currently running the RX8 w/2250 truggy motor on hyperion 4S 5000mah 25C and 35C batteries. Can't finish a 15 minute main right now. My last attempt ended at the 14 minute mark due to low voltage. My lipo was a little puffy, but went back down to normal after it cooled. 5 to 10 minute runs usually end in very acceptable temps across the board.
I am debating on either a 6S 4000mah setup with a 1350kv or 1580kv motor or a continue the current setup but with a 6900 mah 4S battery. The puffy lipo has me thinking about dropping the 4S altogether, I mean, this truggy is pretty heavy to begin with.
Also thinking of switching back to an MMM if I go 6S. Just had an RX8 go bad in my buggy with nowhere near the demands this truggy requires. 6S may be pushing it.
I have the Tekin 1550 with 5s 4200mah Hyperion and I cut the throttle back to 90% for the mains and I am able to do a 15 min main. I cut the throttle back some because it forces me to be smooth and consistent. Too many guys think they are fast but they crash in every corner.
How much does your xt8 weigh? Mine was the exact same weight as my buddys losi 8t 2.0 on 4s.