Mud motor hot rodding: thoughts and current practices

Mini Bike & Go-Kart Parts

How fast did the evo go?
I had it on a totally wrong vee hull, but thats what I needed for where I had to go once I got out of my very shallow bayou from my boat ramp. I never gps'd it but it got that 17 ft great lakes walleye hull up to plane in no time and would haul a few hundred pounds of fish/crabs/frogs/etc, myself and a few buddies in with no problem. worked my shoulders real good too lol The guy who had it orginally had it on a 16x54 excel hull i think. believe he said he had it 55-60 mph per the gps. there were buddies of his that had big stroker evo's on there's with chopper props that were much faster then his he said. there is a video of him runnin this when he had it, he looks like a typical biker with long hair/beard but older so some was gone on top lol


Well-Known Member
I'm wondering how hot it ran...

Boat engines are a lot like aircraft engines. They are run under heavy load for long periods of time and that's why they typically don't make big power numbers given their displacement. Power produces heat and heat has to be dissipated by the cooling system. More power = more heat. Utility engines aren't even supposed to be run at their full rated power but intermittently. 80-85% load is often the maximum continuous that won't void a warranty.

Now think about increasing the power/heat by 50-100% and running it at 100% load for long periods. That's why people who mod their mud motors often blow them up.
@65ShelbyClone That matches my findings exactly. People really called me crazy for years thinking their little go kart engine could handle it, but nope. I just run these bone stock now. the engine is running dog hard even bone stock. Thinking of building a displacement speed hull only boat just run at hull speeds all day long up and down the river. That'd be super easy on these engines.