Nissan 15hp NS15D2 Performance

[Technologic80]

I have a 15hp Nissan 2-stroke outboard, NS15D2 that I am curious about doing some performance upgrades.

First, I used to have an older 15hp Nissan outboard (2-stroke as well) that was a ROCKET ship... that motor was ridiculously powerful. This newer one I have acquired definitely does NOT cut the mustard, compared to my older one that I sold. I am wondering if it is possible to change the carburetor or the throttle cam or something, to the 18hp model, and in essence unlock the power of 18hp?

I know you can do this with the older 9.9hp 2-strokes, but is there a reason it cannot be done with bringing the 15hp up to 18hp? Any help is appreciated.

 

[pvanv]

No. The 18E is a different block.

 

[Sea Rider]

Yep, different horses. What you can do to take all the jiuice out of your current 15 HP is : install an induction Tiny Tach, Hardline Tach go for a wot spin you alone with lightly loaded boat on flat calm, no winf waters and check achieved max wot rpm. That engine revs at 5200-5800 rpm. Knowing your wot numbers will know if in need to go for a +,- pitch and by how much to be at or close to ideal 5800 rpm.

Which boat type is yours ? Other points to have into consideration, hull type, max load, engine height, trim angle, deck weight distribution, prop pitch.

Happy Boating