HELP!!!! In 8,000 M & X's In Owners Hands............

[arknoah]

If you buy new above 25-30hp or do, you have to have it dealer installed or you don't get a warranty. Most places won't even sell it to you.

Never knew that. Something to think about if we ever purchase a 26 X or M.

[vkmaynard]

Not every dealer supports those rules. Our self installed motor is fully warrantied by our great dealer.

[ualpow]

My 2000 that I bought this past spring came with a 30hp EFI Mercury. I was worried at first about being underpowered but after my first outing I feel satisfied. I can hit 13.5 MPH empty ballast with 3 adults on board. I have no problem maneuvering around the marina with board and rudders down. Even with the 12.5" x8" prop I can stop the boat, pull in the bow or stern with no problem. My smartcraft monitor says I used 3 gallons of gas (6 day trips) this season. Of course I mostly sail. I haven't encountered any bad weather or heavy waves yet and that might change my mind if I can't control my boat safely. Although that would probably be more because of my lack of experience than having a larger motor. With the cost of these new outboards I could buy a used waverunner and tow it when I have the kids with me and also use it as my dingy to get to my mooring. (which I don't have yet)
On the planing comment, I thought planing was anything over hull speed. Or is that considered plowing until the bow starts to drop? I'm not a naval engineer, but I did stay at a holiday inn last night....

[gyroplanes]

I'm not a naval engineer, but I did stay at a holiday inn last night....

I thought I saw your MAC in the pool.

We have a few slips on B dock at Hammond Marine, you could be the 4th powersailor MAC there (my and 2 )

[Catigale]

without rehashing a major thread war, you do need more conditions than just "above hull speed" to get on plane....you probably need at least a 75 hp to actually plane these boats unless they are stripped of weight.

[DaveB]

Ya and so far I haven't found a dealer in SW Florida that will put on a Outboard with full warrenty over 50 hp for the Mac.X.
Best I could do was thru Bass Pro. at $5150 for a Merc.50 high thrust, total $6300 with tax,cables,shift lever,install and prop. Will include a 5 year warrenty.
Way I look at it my days for installing a 90 hp Suzukie outboard is over.
Dave

without rehashing a major thread war, you do need more conditions than just "above hull speed" to get on plane....you probably need at least a 75 hp to actually plane these boats unless they are stripped of weight.

[mastreb]

"Hull speed" is the speed at which a hull can plow through the water under sail. It's easily calculated for classic hull shapes. Above hull speed, a boat spends much of its energy attempting to climb the bow wave, and so fuel consumption increases dramatically. This climbing of the wave is what limits sailing to hull speed--as soon as a significant bow wave forms, wind will not under typical conditions create enough power to climb the bow wave.

Planing occurs once a planing hull has enough power to climb the bow wave and remain atop it. This creates a dramatic drop-off in power requirements compared to moving at the same speed while plowing.

A hybrid hull like the is designed to both plow and plane, so it gets up on a plane later than a powerboat. Classic sailing hulls are not stable on a plane and have heavy keels that prevent them from ever getting there.

So the definition of "planing" isn't necessarily when you feel the wind in your hair and the boat scooting along like a powerboat, it's when fuel consumption per knot falls back off after the transition period from hull speed (6.5 knots in a Mac) to planing (something like 13 knots, but it would need to be tested empirically). I think 13+ knots is the planing speed for macs because these boats seem to speed up pretty rapidly once you get over 12 knots, and that's where my fuel consumption drops off under typical load conditions.

Catigale is essentially correct: Under typical loading conditions, 50hp is certainly not enough to maintain 13 knots. Keep in mind that the bare boat will plane much faster than a boat with 1000 lbs. of weight in it--Powerboats rarely if ever have that kind of weight load so their HP to speed ratings are much more consistent, but we tend to fit out our boats like RVs and they weight a lot more.

50hp is the minimum to get an empty Mac over its bow wave. 60 hp is the bare minimum for routine planing under light load, 75hp will do the job under any typical loading, 90hp is probably the safe maximum but I'll let people who've got engines this size weight in for that.