Yeah they can pump it up to almost 200HP.  If you get the high compression Helicopter pistons you can pump the 0360 up to 225.
Pitts S1C  Single seat, fixed pitch prop, 85 - 180 hp. Two ailerons,
           flat bottom wing.
Pitts S1D  Single seat, fixed pitch prop, 85 - 180 hp. Four ailerons,
           flat bottom wing.  S1S fuselage (longer than S1C).
Pitts S1S  Single seat, fixed pitch prop, 180 - 200 hp. Four ailerons,
           symmetrical wing.
Pitts S1E  Like S1S, but homebuilt (E for Experimental)
           symmetrical wing.
Pitts S1T  Single seat, constant speed prop, 200 hp and up
Pitts S2S  Single seat, S2A fuselage, constant speed prop, 260 hp
Pitts S2A  Two seat, constant speed prop, 200 hp
Pitts S2E  Same as S2A but experimental
Pitts S2B  Two seat, constant speed prop, 260 hp. Slighly larger
           fuselage than S2A.
Pitts S2C  Two seat, constant speed prop, 260 hp. Redesigned ailerons
           and rudder.
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