Nissan 40hp 2-stroke, getting more power out of it?

My fiance has an old Selco 14 feet boat, at the back there is an Nissan 40hp 2 - stroke engine. It is an two cylinder engine with 496cc displacement.

We are looking for some more power out of this engine since it really struggles to get up in plane. We rasied the engine at the transom and fiddle around with the trim angle and it respons normal to the adjustments. Otherwise the engine runs good, and the throttle opens all the way aswell.

Bottom line is, there isn't enough torque in this engine. Is there something I can do to get more power out of it? Any built in restrictors?


Best regards,

Tobias

Anyone got an idea?

You likely have an old M40C. You are at the limit; no carb upgrade, etc., for that setup.