I have the same prop on an 05 Cougar FTD,DC. And I am running the same.If you have info on some thing that works. Please send the info back.I was in a Cougar FTD SC. with a 225HO. And it run 78.1 on GPS.
GuysRunning same prop on 201 Stratos Pro XL same mtr. Was getting almost same speed rpms you were. Sent prop to Boger he got me 300 more rpm and got me to 73.4 gps. He said prop was close to a 28 and had hard time getting it down. He told me to run the 25T1 with the load Iam running.
Motor? are you running a hpdi? I am running a 250 hpdi on a puma no problem exeeding 5500rpm if wanted 76mph heavily loaded at 5500rpm. actually going to try a bigger prop this weeked. I also have a hydrolic jack plate.Eddiewww.proschoicelures.comEddie http://www.realityoutdoors.nethttp://www.proschicelures.com