none racer needs advice!

[johnsonm50]

John, Theres alot of differences in the basic 31.8 blocks. I doubt you'd see 10hp off the bat but some would be likely. Be sure you dont have a plastic venturi insert in the carb or a restricted flow intake [hole smaller than the carb] you can look in & see w/a flashlight w/the airbox off.

There is alot that can be done but just trying stuff will usually not help. The 35 carb & 35 timing spec can help but some 35's have a different crank etc. BRP parts catalogues is a good place to do # comparisons. It will take some time but you can check your year against the 35 of same or other years. The biggest increase Ive ever seen is from a good gearcase 1st then a good prop 2nd.

The OMC's need to be timed right, syncronized well [timing to carb response] & there is an econo-mizer adj. -be sure you are getting full throttle. From my experience you can modify all you want, the big obstacle is the reeds. I've put old stock powerheads on modified lowers & found them to be within a mph or 2 of a fresh mod. Its more about getting all things working well at the same time.

The B1 bombers are the 22ci OMC for the most part, very similar design but smaller. They were run in B1 modified as megaphone motors on a Hot rod or Merc H lower. Thats changed now but modifying them has become popular. The 28-J is a 31.8 & is pretty fast.

[jeff55v]

Years ago, I played around with an Almarine Seafire that I owned. It was a 9 foot long play boat similar to yours. It was a lot of fun. I installed a strong 35 evinrude with a stock gearcase. I milled the head and shaped the gearcase. I tried numerous props, and worked on the setup for hours. The top speed I could get out of it was 40 mph. And that was under IDEAL conditions. I concluded that in my instance, the boat wasn't designed to lift up out of the water at high speed. I had to rely on the engine trim angle to try to lift the boat up and out. The little 35 was wasting too much of its limited power trying to change the natural running angle of the boat. It would have taken much more hp than I could float on the back of the boat to improve my speed beyond 40mph.
But it was a lot of fun to play around with.
Food for thought.

[minispeedtoth]

I'm going to look at a merc 50hp next week... it needs some work but that's ok, I might just strip it down and get the head redone over and look for a chopper blade..

[jeff55v]

Do you have any photos of the bottom of your boat?

[ZUL8TR]

Head redone

I'm going to look at a merc 50hp next week... it needs some work but that's ok, I might just strip it down and get the head redone over and look for a chopper blade..

What do you mean head redone? I believe these Mercs have the head cast with the cylindere and the back cover on the engine just exposes the water cooling area. Or do you mean rework the cylinderes?

[stevegray]

Why not make it "Unique"? Inboard, Jet Ski style?

[minispeedtoth]

I don't have any bottom pics, but its kinda like a mini tri-hull.. handles like a little go kart in the water.

[minispeedtoth]

inboard jet ski would be cool, but I'm not really into the jet drives.. I love outboards, especially ones like everyone runs on here, love a small motors that are fast, maybe I like the underdog thing. Everyone on my lake has big block stern drives, theres only one hydro boat that my father had build for a guy, and its fast... I want to get my little toth as fast as possible!