Thread: Ir runs! Thailand outboards for the win!

Good job!! Wonder how many hours it's gonna run?

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Well, it's already running better than the built Predator I had last year. I started with a better base engine, something built to much tighter tolerances. Then I scaled back the power, so I'm not pushing it as hard as the old Predator. It should last a long while.

I built it by increasing the efficiency more than making power. For instance I chose a flat-top piston to increase compression about half a point. It should be about 9:1 to 9.5:1 now. I added an extra long rod +0.080 to make for better rod ratio. That will put less pressure on the crankshaft whenever it changes direction. The flat-top piston is -0.080, so the overall length is standard, but the rod ratio is optimal.

Lighter rod, piston and flywheel combo means the engine uses less energy to keep itself running: more available power to turn the prop.

Really what I've done is build a power head comparable to most marine powerheads with similar displacement.

Neet,. !.e, u bored & stroked it!

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rebranger, in a sense I have. Most guys who want a bored and stroked powerplant buy a 212cc Predator from Harbor freight. My powerplant is only 196cc. Dynocams also sells a 212cc motor which is bored and stroked from the factory with large cylinderhead valves: Racing Cams and Parts | Ducar 212cc OHV Engine | DUCAR-212KIT | DynoCams

The reason I chose the smaller displacement was the Box Stock Project motor is better built to a tighter set of tolerances to make it easier to build for a guy like me working under a shade tree. The Dyno engine is just as well built, but I they literally just started shipping this engine today.

WoW I don't know if its a lawn mower or a stump jumper LOL It will go where most boats won't .RR

that's pretty cool...thanks for sharing.