Ok so I ran my 272 with a 454 magnum EFI, stainless marine exhuast, and 25 pitch mirage plus prop this weekend. I had a full tank of gas, 6 people, 3 guys 3 girls, and smooth water. The max rpms I got to was 4100. The GPS read 52-53mph. The mercury marine prop selector tells me I should be running a 21 pitch. Your comments are appreciated.

A 25p is definaly to big. You should shoot for 5000 RPM. If you run it loaded down with weight a 21p might work best. With a light load a 23p might be better. Also when the heat and humidity go up you may loose 200RPM. Do you have it trimed up high enough?

I will most likely always have at least 4 people on the boat. She was trimmed perfectly and running smooth just not enough power to spin the prop if you asked me. I bought the boat up with a 25 pitch on it.

Try the swap shop, maybe somone will want to trade.

Im gonna try a friends 23 pitch this weekend so I might just do that if the 23 works.