Light is right, but I believe Merc's new 115 Command thrust is much more motor than the etec 90. I think you'll find it closer to the etec 115 in performance. It's a 2.1L with gearing that allows more considerably more prop. I'm pretty certain the etec 90 would perform similarly to your Yammie. A hair slower WOT perhaps, but excellent cruising torque curve and economy, incredible economy through manatee zones.
"bitsamonkey" had incredible numbers from the Suzuki 90 on his 18,also...
http://www.classicseacraft.com/commu...ki+performance