Transom HP limits

[T.R. Bauer]

39 mph is flying along way too fast! But, if somebody was looking for a 30 mph cruise or so, that would put the 140 at less than 80% work capacity as the 22 would theoretically go a tiny bit faster before it burns up in the atmosphere after it launches into outerspace. Kidding aside, I suspect the 115 Suzuki would be only be a hair slower in real usage since they are very similar in so many ways. If you can stay down below 80% power output, your engines will last and last. How do I know??? Well it's a very rare day I push mine past 5k RPMs and they have nearly 3k hours on them and are still going strong. A Volvo marine mechanic once told me that 80% of the wear an engine has is during the last 20% of the throttle. Beats me if true, but I have lived by it for multiple boats and for many different engines.

Repowering is a serious deal and how someone uses their boat should absolutely factor into the power equation. I feel twin 45s or a single 90 is enough for fishing trip, but wish they comfortably went a bit faster when the seas are flat as they are screaming at 30mph - a speed where the boat is fine. How much does this shorten outboard life? I don't know, but some for sure. If you just went by sound, you'd swear you're going 100 mph!

When fully loaded for a camping trip, 90 hp barely cuts the mustard and turning a 3 hour boat ride into a 5-6 hour boat ride because you can only travel 18 mph at 100% throttle is just rediculous and hard on engines. On the other hand, 90 hp is more than you will ever need on a Seward trip, because the seas are going to suck and you can just about count on lots of 10-20 mph usage. And, that's if you're lucky!

Anyway, I'd choose the engine that makes you happy with your boat for what you are using it for. Someday I'm going to repower mine, and that is a big decision and I'd rather shoot over than under.