have a fresh briggs limited flathead just built by one of the best engine builder in the Carolinas, CPR by dane and chad porgiski, we have not ran the engine but they built it and dyno it, cannot answer any questions since i am not the builder but i do know they turn out in the 22-24 hp range, this builder does not build junk, thet do have a web site CPR racing engines, if u want to pickup instead of paying shipping we r located between Gaffney/Cowpens.SC