Not to many sailing cats work that well as faster speed powered cats as they tend to squat in the bum.
This can and has been overcome on some production cats that have been modified for power (lightwave, perry as an example) by reversing the rocker in the last couple of metres and making a flat.
This is what I have done to my hullshapes, plan
on 10 knot cruise
@1800rpm 55hpx2, 14knots on the perfect day at full noise
Even so, these vessels work best at up to 14 knots, after that, you really need to change hull-shape to a full blown displacement
powercat type (double canoe ends with bustle)like Tenants IMHO.
There is a good article that I will try to find by Tenant where he discusses performance of sailing cats under power and where they start to become inefficient
here it is
and a snippet from the article
"When many of the French catamaran companies decided to get into power cats they just fitted larger engines into their sailing hulls, probably because being production boats they had the moulds handy. This is fine as long as you are not going to exceed around 15 knots. Beyond this speed the hulls start squatting and assuming a bow out attitude. The sailing boat hull form is not really suitable for a displacement power cat with any performance or long range aspirations. They are essentially trying to go up hill and require increasingly large amounts of horsepower to move."