1994 31 sonic 502 mags how fast should it be on gps we only got 62 and its spinning 23 4 blade props at 4700 rpms. how fast should this boat be and what props should it spin.

thanks rick

My 1990 with 454, 365hp did 67 on gps with 23p Mirage 3 blades @5000 rpm. I think you should be in the low 70's.

You have to get up to 5000 rpms on 502