2 questions

CHRIBS · 30 May 2018, 15:28

Hi I have two questions I have a Honda 20hp OB and firstly is there a way of increasing the power a bit like chipping a car ? Secondly has anyone had experience of stabilising fins and if so which are the better ones for a Honda ? Many thanks

Fenlander · 30 May 2018, 16:54

The Honda 20hp is the higher power version of the 15hp which shares the same powerhead/capacity... it is sometimes possible with some makes to increase from lower to higher HP for a given powerhead but not within the realms of DIY to tune the 20hp.

OB tuning is a very niche specialist field and usually only undertaken by those for example racing Thundercats with a certain OB make (Tohatsu I think).

Re fins if you mean those that clamp or screw to the AV plate they are only of use to an outfit that has problem planning due to excess loading etc. They should not be needed for your outfit. I have had them supplied with OBs I've bought and trying them I've found they give odd steering... can in some sea states produce unwanted trim attitude... and they add drag which lowers top speed.

Fenlander · 30 May 2018, 18:18

Now you've found you have a spun prop bush to replace I'd get that sorted and have some time out with the outfit to see how it goes with that improvement.

CHRIBS · 30 May 2018, 18:57

Great yes the guy at the marine place says it needs a new prop ? Can the bush just be replaced or is it a new prop

jeffstevens763@g · 30 May 2018, 19:20

A different prop might help, you need to know what you have now and what RPM at wide open throttle

Fenlander · 30 May 2018, 22:14

Some places will just replace a hub but by the time you've paid potage both ways a new/recon prop may not so much more.

Try these guys mail or phone and they will advise...

Propeller Repair - Specialists - Castle Marine