I've always thought that 2-stroke engines performed better than 4-strokes because they have more torque at nearly all ranges and can run at higher WOT. This test surprised me. I am not sure how truthful this test is, but I thought it might be interesting to see. I just can't help there is something wrong with the Yamaha.
Would have liked to see them drop the pitch on the Yamaha to see what improvement it would make. Something does not seem right with the Yamaha. Either wrong gear ratio in the drive or some type of mechanical issue?
It seems to me that this might be due to how those engines make power. 200HP is not much for a boat of that size and if the Yamaha makes most of its power at high RPM's, it would have more trouble getting out of the hole.
1975 Trojan F36 Convertible, Twin Chrysler 440's 2014 West Marine AL360 Inflatable, 1966 Mercury 6HP, 1992 Mercury 20HP
Running the engines off-center isn't a good way to test-- When I lost the starboard drive in my old 24' Reinell, the port engine- a 318 Chyrsler V8 mind you- couldn't get the boat past displacement speed. I'm surprised the 'Rude got that boat on plane... and I'm not sure which, but one side will be working harder to get planed out because of torque twist and possibly gyroscopic forces. They need to either swap the engines or even easier, just mount them one at a time down the centerline..
If you watch the whole video, you'll find that they did try lower pitch props and they swapped the engines from side to side, made no meaningful difference.
I'm astounded that the Evinrude 2.7 liter 2 stroke only makes 150HP. That's really low for such a big engine, especially a 2 stroke. The late 1970s Merc 2.4 liter 2 strokes made 200HP with carburetors.