silly question

[Noddy]

I have a yamaha 4hp longshaft as an auxillary for my RIB which is hardly every used(thankfully!). I have just bought as small "Walker Bay" Dinghy for messing about in which will give the engine some much needed use. The dinghy is listed as suitable for a short shaft outboard. Apart from being deeper in the water am I likely to encounter any problems with using the longer shaft length?
Martyn

[Searider]

There will be more twisting on the transom as the force line of the propeller is lower. This may tend to lift the bow more as well. Will also cause more drag and spray. Will be good to exercise the engine though.

However, my brother had a longshaft 7.5 on a 2.8m humber SIB with no problems. One benefit is that when the boat flies the propeller stays immersed and you don't lose drive

[Noddy]

Thanks Duncan