Long or short

 I have a Polycraft Tuffy fitted with a Parsun 9.8 hp short shaft (don't judge me it came with the boat) but I am finding it a bit hard on the back without power tilt and trim. So I thought that I would look for a 15 hp (maximum rate allowed) with electric start & power tilt & trim in a short shaft but all of the main manufacturer's only seem to make electric start & tilt & trim in their long shaft motors. So I have been toying with the idea of fitting a jack plate to lift the long shaft motor up.

Any way I did some measurements and I always thought that to have a short shaft your transom height from top of transom to lowest part of hull should be 15" but mine measures almost 18" The Parsun cavitation plate lines up with the bottom of the hull but from the cavitation plate 15" comes to the top mounting bolt hole again I thought that you measured from the cavitation plate to where the mounting bracket sits on the transom.

So are the Parsuns short motor actually longer that the standard 15"?

The present set up seems to cavitate under certain running conditions.

Any way I guess my question is would a long shaft Suzuki/Yamaha be suitable for my boat and if necessary I am happy to fit an adjustable  jack plate to raise up that extra 2" approximately. or if anyone knows of a short shat 4 stroke 15 hp outboard with electric start and power tilt & trim can you please let me know. 

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