Castle, HPI and Traxxas all say the 2200 is fine on 6s, although higher rpm than I like for off road, I think it is fine on road with proper set up. I ran a 2200 on 6s in an Ofna GTP geared for about 55mph, it was a blast... smoking burn outs that left black marks on the road.
What was your gearing and temps on the Ofna?
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