Repower
 

Considering the 2015 115 Mercury 4s for my 1985 20 SF. If anyone has any experience with this motor or setup what are your opinions?

The Tee Top and windshield may hold you back a little, but I would guess you would be in the neighborhood of 30-32 mph WOT with a perfect prop. Probably cruise comfortably at 20-23 mph and get 4 mpg. Unlike the Keys we make a lot of 60-80 mile days when we go bottom fishing off shore because there is very little structure inside of 45' off of Tampa. Good milage helps you use the boat more often. Just sit back and enjoy the VDH ride.

What is the weight of your hull? I would expect mid 30's for a standard gear case, faster for a command thrust Model. Merc performance reports put a command thrust 115 with Enertia prop on a 3300lb scout boat in the mid 40's top speed and best economy of around 6 mpg at cruise. I'm hoping to have some numbers in a week for a command thrust and powertech 14.25x21 pitch prop

Definitely not going for any speed records, distance and fuel economy is what I am after. It's an 85 year model. not sure of the weight. Want to put a platform on the back, 60 gal tank shifted forward, remove the casting deck and put a fish box cooler up front and a livewell type leaning post/rocket launcher.http://cmmarineproducts.com/Product/...0-c8b31cb16eac

The leaning post.

I suspect a slightly higher top speed. But I bet a 17P prop is close to what you want. I run a 15P on a yamaha F100 on a 75 20MA. And hit 33MPH at WOT. I suspect you will do a bit better.

I left my casting deck, but made it shorter so I could slide my console forward, batteries in the console and also put a new 50 gallon tank as far forward as it would go. I also have an aluminum leaning post And a closed transom with fiberglass bracket. My Boat will probably be lighter than yours as i haven't added a livewell or wash down system yet, those are future projects

[IMG]http://picup.su/upload/150418/600_18289_82373.jpg[/IMG]

Looks good. Have you splashed her since the new motor?

Not yet, Just brought the motor home today. Still have to rig it. I floated it with simulated motor/gas/gear weight to make sure she was ok with it and she sat perfectly.

I expect it to be a winner. Lightweight w appropriate displacement to make up for being 4s. Good luck! Look forward to hearing performance nos.