You are talking about the ex-spec motors correct?
We ran those in a stadium truck class over jumps on carpet with 1800mah pack battery limit. You could make the 5 minutes no problem and they worked great. Heck, we got into it and hunted down RC1700 cells to run in the class, but a good stick pack worked just as well.
Tuning wise That motor uses standup brushes right? ( been awhile) . I think alot of guys if they had a reserrator were cutting 767s to standup position and using them. Also a spring setup (fiddlestick settings) of 7.0+ , 6.5- worked very well in the class. 1 drop of tribo on the comm or 1 drop on the positive brush, though I don't think what side it was on made a difference.
You can also try experimenting with different drill holes in the brushes as that I believe also upped the power.
We also limited tires to rubber compounds (no foams)
That brings back memories!
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