sib to rib...a few questions

[jrzmotorcycle]

Hi fellas!!! Say, I have a 11 ft. Sib currently, with a air floor. (crappy) floor...doesn't matter if its pumped up to 12 psi or 100 psi...it still wobbles like a fish out of water. So..I'm looking to get a RIB. I'm looking at a Achilles hb350lx. It is a 11 ft. 6 in. Boat. On my 11 ft. Sib, I would get up to 22 mph. Max speed on my sib with only myself aboard, and 20 mph with 2 big guys. 2 total in sib with a 15 Hp. DF15 Suzuki 4 stroke. My question is, will I gain more speed and preformance being a RIB, with the same engine??? Also, who makes Achilles inflateables? Where are they made? Are they one of the best on the market? I'm knew to ribs, so any info or advice would be welcomed. Thanks a bunch. Joe

[Poly]

What you might gain in speed from a more rigid hull (so possibly 'nicer' running surface) is usually wiped out because typically they have a more v-shaped hull form (better for waves, worse for speed from same power) and are usually heavier.

3.9m rigid hull here with 20HP 2 stroke, console etc. Boat weighs 120kg, Engine 50kg, Fuel, anchor, crap, etc probably makes it 250kg+crew. It will do 22 knots with just me on board. 2 adults + 2 kids + lunch etc and its 20 knots on a very nice day. [these speeds are knots not mph].

You probably won't see much difference in speed.