Do I Need To Repower??

[Mac Ziggy]

Even with an E-Tec 90 and a 14 X 11 prop, I still had the problem of “plowing water” instead of plane. The worst part was, the bow was so high, it made it difficult to see where you were going. Lightly loaded or shifting weight did not make any difference.

I eventually put a hydrofoil on the engine. The bow came down and I could see. The engine runs at a lower RPM and I’m sure it uses less fuel. I can do the advertised 22 mph. I do not think the hydrofoil is the best answer, I think the wedges are but I have not changed yet.

I think the M and maybe the X have transom angles of 12 degrees. The E-Tec specs are at 15 degrees. I think the engine was pushing down the aft as much as it was pushing the boat through the water. I think the wedges will allow the correct angle for the engine.

[pokerrick1]

Get Suzi over the Honda for sure J.....

Honda 90 4s efi = 1496cc
Suzi 90 4s efi = 1950cc

I said it before, I'll say it again.... ITS TORQUE THAT MOVES THESE BOATS



G

AGREED - - - and the E-Tecs are torqued better for our boat - - - that is the main reason Roger chose that brand (as well as price, fuel economy,
emissions, etc. ad naseum) It is not JUST all about HP.

Rick

[Dimitri-2000X-Tampa]

No disrespect intended, but there is a lot of mis-information in this thread. If you are "plowing" with a 90HP, you have done something seriously wrong.

I don't know about the M boats with their deeper V shape hulls, but I can get my X boat to plane at 11-12 mph and with my 8 year old 50HP Mercury BF (14X10 prop), I have hit 19.5 mph before. Granted, that was probably a good day, but I can always hit 18 mph lightly loaded on any day. I don't see many sailboats that can even hit half of that speed. Btw, when I say "lightly loaded", I'm talking about passengers. My boat is actually very well equiped with lots of heavy toys, ie, microwave, pressure water system, large water tank, stereo/tv system, two batteries, 2 anchors, etc.

With my whole family of 7 aboard, and a few more supplies, that speed drops to about 16mph. I have seriously thought about re-powering too, but frankly, my engine runs well and I can't see plunking down 8-10 grand to pickup an extra 5-10mph...when I am out cruising, I'm not trying to get somewhere fast. Now, when the BF dies, thats a different story, I'll get a bigger motor.

My advice for you guys who don't think a Mac planes with 50HP is to go buy a speed boat, you will be much happier. Heck, I have a 160HP jet ski which will hit 60mph...btw, even that screamer will plane out at about 14-15 mph even though it has a deep V and a very short hull length. I went to a ski show a couple months ago and even those 400HP ski boats were planing at about 15-16 mph, in fact, most of the stunts were done at slow speeds. Granted, they were pulling 10 skiers at that slow speed but the only time they got up much over 20 mph was when they were pulling the barefoot skiers, which need a faster plane...around 35-40 mph I believe. This was in a very small lake so they couldn't afford to go too fast. Btw, you can't "plow" on water skis. The moral of the story is that there are slow planes and faster planes.

[beene]

The moral of the story is that there are slow planes and faster planes.

Ya... like a C152 vs F22 Raptor

G

[Currie]

One thing I haven't seen mentioned here is trim-angle. Perhaps you've all found your optimum outboard trim-angle already - I know I didn't think of it right away. I trimmed my Suzi 50HP to full-in the first couple of times out. Mine will trim in, past vertical by about 6 degrees. This is not optimum, even with my whole family on board. It forced the boat into too much of a plow. The ideal trim-angle changes with load, so you should always experiment on an outting with new conditions. Trimmed-in too much it plows, trimmed-out too much, it porpoises (lurches up and down).

Just want to make sure you're getting the best use of your current HP, before writing it off

Cheers,

~Bob

[ChrisP and Pam]

Well,
There was a 2006 90 etec on a 15' Glastron for $5,000 and I was going to swap motors and sell the Glastron with my 60. But, it was in Battlecreek, Michigan. I did think about making the drive but passed on it.

Boy, that hurt!

Pam likes the idea of a new motor though. So I think that's what stopped me.


Beena Said,

Get Suzi over the Honda for sure J.....

Honda 90 4s efi = 1496cc
Suzi 90 4s efi = 1950cc

I said it before, I'll say it again.... ITS TORQUE THAT MOVES THESE BOATS

Thanks for the insight on that Suzi. I had been overlooking them but I'll look again.

[Chip Hindes]

I've said it before, I'll say it again.... ITS TORQUE THAT MOVES THESE BOATS

Say it as many times and in as large letters as you want. That does not make it so.

Torque is good for many things, but when you are discussing top speed (only) HP is what matters, not torque.

[ChrisP and Pam]

Dimitri said:

I don't know about the M boats with their deeper V shape hulls, but I can get my X boat to plane at 11-12 mph and with my 8 year old 50HP Mercury BF (14X10 prop), I have hit 19.5 mph before. Granted, that was probably a good day, but I can always hit 18 mph lightly loaded on any day. I don't see many sailboats that can even hit half of that speed. Btw, when I say "lightly loaded", I'm talking about passengers. My boat is actually very well equiped with lots of heavy toys, ie, microwave, pressure water system, large water tank, stereo/tv system, two batteries, 2 anchors, etc.

With my whole family of 7 aboard, and a few more supplies, that speed drops to about 16mph.

So you can't get 22mph?
Chris

[Highlander]

Yes Chip

That's right HP gets you the Top End Speed on a lightly loaded boat but with no torque & a heavily loaded boat you'll need a 10 mile run to reach it, if at all !!! . give up a little hp say from 115 to a 90 with more torque on a heavily loaded boat the 90 will be faster & burn less fuel & be able to cruise at a lower speed & lower "rpm's"

John