worth attracting Talbot to this one, he owns one.... I could have a stab at it but it would only be a guess based on a similar sized competitor /forums/images/graemlins/grin.gif
I used to sail one. A great, safe, family boat.
With twin Yanmar 1GM10s I cruised at 5 kts, flat out just over 6 with a clean bottom.
She'll sail as fast as you dare on a beam reach and surf at 15 kts with a following sea (done it, knicker gripping stuff).
Sailing to windward I'd motorsail with the leeward engine running, thus minimising leeway.
Sailing speed is around 6 to 7 knots with a F4/5 on the beam. Did this last year crossing the channel. Close hauled ideally needs an engine to reduce lee way etc. Motoring speeds depend on the engine(s) fitted but can range from 4 to 6 knots cruising. Some had twin 15hp fitted which gave the option to be able to cruise at 6 knots regardles of wind and waves ... If you need more information let me know
the catalac hull form is a deep-V with a considerable amount of keel rocker. it is a wave making shape that is limited to hull speed so hoping to go a lot faster with big engines is not feasible. under sail, any hull form will surf (i.e. be carried forward by the surface current on a wave) but planing is something quite different and i would be very surprised if it is ever achieved in a catalac. ok talbot - tell me i'm wrong!