I had a 160HP O-320 with a metal Sensenich prop in my -4. It was reasonably smooth, but could be better. I did not have it dynamically balanced. I ran a 3 blade Catto on it for a while and that was very smooth.
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Glasair Sportsman (Bought disassembled, now flying)
RV-8 Tail, QB Fuselage (Sold)
RV-4 (Bought Flying) (Sold)
RV-12 120018 Flying (Sold)
RV-7 Tail, Wings, Started Fuse (Sold)