Hotrodding Outboards

I just picked up a nice hull to replace my clapped out one with 115 Merc. This hull has a 85 Evinrude on it so short of putting my Merc on the hull I was wondering about inexpensive hop up tips. Boyesen makes reeds and the intake (silencer and bottom engine cover) looks like it's quite restrictive. Does anyone know if the 85 just has smaller carbs than the 115? Any other ideas? Thanks!

 

From what I know about outboards it's not the best to do any hotrodding to them. If you want more power just put on a larger engine. You'll like your merc better anyway.

lumiecraft

 

Does anybody know about outboard hot rod sites? Thanks!!

 

Can the boat handle the extra power? It is the first thing to consider.

 

First is the boat designed to be a hot rod. Most are not. It's not a good idea to over power a boat that is not designed for the extra power. You might get away with some extra but not much. From 85 to 115 you are pushing the limit. Second is the transom a wide transom or narrow? Wide transoms are better able to handle larger engines with less sinking in the back. Third, is the transom strong enough to handle the extra power. Not only the transom but the bottom and stringers must soak up some engine torque as well and if any of those are marginal I would not over power the boat at all. But still the best way to get more HP is to get an engine with more HP. That Merc 115hp unit should not weigh much more the the cluncky 85 that's on it now. Merc's are light engines with tons of power. Not saying the Johnsons or Evinrudes are bad. They are very strong and reliable as well. But with the Merc will the boat handle the extra torque. I for sure would not go beyond that 115 hp Merc. That's a load of power. I plan on doing the same as my boat can handle the extra 30 hp. Weight and torque are not an issue with my boat.

 

Sweet looking boat! How fast will it do? I have not tried this hull with the 85 HP yet and I imagine it will
pull pretty good as is, so wait and see. I was really just wondering what some of the tricks were. Only
hot rod work I have done on 2 strokes was my CR480 dirt bike. Wiesco, Boysen, porting.

 

You didnt say what the hull is? Now I know im going to get it here but I bought a boat once,--- 18ft rated for 80HP It had a lovelly transom and a good slop well glassed in. I just didnt see why it was rated for 80 hp. I bought a 150Hp Merc Black max. ( yes it was a long time ago) It was a great bare footer. My mate bought it from me and fitted a 200hp!!!!!

With a 19 pitch it was a good pull for bare foot flying beach starts. With a 17 it would literally leep from the water and plane instantly.

You had to warn passengers before take off or they would end up with there face in the battery box. You had to be carefull with it. I would not ever pull the ski jump with it for instance.

World champion bare footers used to visit the club occasionally,--They thought it was the buisness. They prefered it to the Mastercraft. It was so much fun.

I would hate to live in a country where you could not even uprate your outboard with out worrying what Hp you might have. I thought America was the land of the free.?

Do you have Ferrari's in America or are they too dangerous.

 

It's a 15' Canaventure. Looks like 1977/78. Glass work looks nice, not a chopper gun boat. Looks real solid with no gelcoat cracks. Not as wide or deep as my 16 1/4 and I remember without the dole fin and using a ski polethat boat would shoot for the sky. Well I won't say what I think of my Vanguard that after 8 years had two 5' long holes on the edge of the lift strakes under the drivers seat. Pulled the floor out and nothing but dry chop, rotten wood and
a 2" deep pool of clear resin at the rear of the boat. But it would pull us barefoot! After about 150 hours of labor that boat is still stronger and lighter than new however! Maby throw the 85 on it and use it for fishing and the 15 for Ski duty. Weel see!