Raising the engine two holes

My Selva Madeira 40 was installed as low as possible (the highest mounting holes).
I have noticed a long rooster tail and excessive spraying so I decided to raise the engine two mounting holes, that is the second highest position available.

Before

After

After raising the engine the RPMs increased from 5300 rpm to 5600 rpm using Solas 11x17" aluminium propeller and the speed increase was about three knots.
I think the engine can be raised even more as the propeller grips quite well and can be trimmed up without problems.

Here is a video taken after the the engine was raised.