KB is a whole different animal. The effiecency on that blower is twice of the "H"Eaton.
I have seen mid 11's on stock bottom end. But I wouldn't count on that if I was trying to get there.
Bottom line, if you want to use this motor and make it faster. The safest way is a 4# pulley, or a small shot of juice. Other than that you are pushing your luck.
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