Ultimate Utah fishing boat.

[MrShane]

I chose the 115HP because it was the highest state of tune for the block.

Please explain further what you mean by this statement?  Thanks.

Most outboard powerhead blocks are shared with at least 2 or sometimes 3 horsepower ratings.
The changes in horsepower ratings are determined by carburetors/injectors, fuel mapping/timing,and exhaust system tuning.
Jon’s 115 is probably the same block as a Mercury 90 hp, just ‘tuned’ to put out more hp than the 90.
No different than how Mercury, Yamaha, and Suzuki 9.9 and 15 hp kickers share the same block ( per manufacturer) but the 15 hp engines get tuned to the higher hp.