I just want to get an idea of what is out there. What kind of RWHP are you guys making and what transmission upgrades do you have to hold this HP?

I would trust a Suncoast III to ~480rwhp in a heavy truck that gets occassional race duty. 550rwhp is too much in Big Blue.

490-500 RWHP with a Suncoast III............23K miles..........60++++ passes on the tranny so far.........

I think I am pushing a SUNCOAST III limit right now...........:eek:
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I chose a Suncoast III with intentions of holding a TTS Extreme when it becomes available for the LLY. Most of the time I only run an extra ~80 RWHP, so the III is plenty for that duty.