i used to own a 96 evinrude 88 spl and was told it was a commercial engine. not sure what the " spl " stands for but they were all non - oil injected from the manufacturer. was a very good engine for me! ran great for 8 years then sold it for a newer rig.
The odd hp and SPL is for marketing. For example, the 88 spl is a 90, without VRO, and T&T is an add on. They don't want to offer 2 motors with different features, so the one with VRO is the 90, and the one without is an 88. Same motors for the most part (the 90 may have a few more features)