Originally Posted by codprawn
And there was me thinking it was a normal Scorpion RIB - no wonder it did so well stripped out with surface drives.
I think you've got your wires a bit crossed!
The open RIB which I think was HL3 had a single engine and Trimax surface drive. HL4 which is now Mystic Dragon has 2x Yanmar 300s with Bravo 1 drives, and is a standard Scorpion 10m Sports Cruiser, almost identical to Seahound 4. HL 5 is similarly powered, although I think with the later 315 Yanmars, and Bravo 1 drives again, however it's the stepped hull and lighter build that give the advantage. There are a few other tweaks and modifications to HL5 to enhance performance...