Posted by tetontrouthunter on 02/09/15 - 2:47 PM
#1
I have a new to me 1986 outrage 18.the motor is a 2005 Yamaha F115 with a 13 1/4"x 17" white Yamaha prop. The guy I bought it from ran it at sea level in Seattle. He had some issues with "porpoising" and installed a hydrofoil on it and said it helped. The motor is mounted all the way down. I will be running this boat at 6000-9000 ft in Wy and also trailering it to Baja. Will I need different props for different altitudes? Or will the fuel injection and computer figure it out? Less O2 up here in WY. As we are in the heart of winter I can not test. Assuming he was getting good RPM's should I move motor up before playing with props? In WY I don't need to go fast but would like good acceleration to occasionally pull skiers. In Baja fuel efficiency will be the priority.
Posted by brwntrt on 02/10/15 - 1:55 PM
#2
Good to see another Teton Whaler on the site! I run a 15' sport with a 75hp Merc on the Idaho side. The 18' Revenge is a beautiful boat. I hope I see it on the water this summer. I've taken my boat down to lake Mojave with both a 15" and a 17" inch prop and also used both on Henry's which is roughly a 6000' difference in altitude. I would guess the difference in rpm at both extremes to be at most 400 at cruising speeds. It's noticeable, but nothing to affect a fun day on the water. I think there's overlapping between the prop change and altitude change, they don't compound each other. If that makes sense. If your going to Baja you probably want to bring a spare prop anyway, so why not get a different pitch and try it out. My boat came with the 15" prop but once I put on the 17" I never changed back. Have an awesome trip! I'm jealous.