New outboard on the market

[Bobby T.-26X #4767]

Sure I can do 15 knots but I rarely am able to go that fast without inciting violence from the crew getting soaked by the spray.
Unless the wind is coming from the right direction, you are not going to be going all that fast, without foul weather gear on.
Jim

i agree with the wind, the spray, and the waves creating a wet & bumpy ride.

i was on the water (the Pacific Ocean) all weekend and was not able to exceed 17 knots under power due to the wind and waves.

that said, i truly enjoy having the extra "horses" so that i can cruise at planing speed and yet only requiring 2/3 to 3/4 throttle.
at 17 knots i consistently travel over 20 miles on a 6 gallons (3.5+ mpg).

Bob T.
"DāBob"
'02X w/ '04 90-TLDI (14" x 11 pitch)
Dinghy Motor: '06 2.5-Suzuki

[DaveB]

Bobby,
Must be nice to have those waves spaced 50-100-500 ft. apart depending on wind.
Us in SW FL. we Sail the Gulf Of Mexico were it is very shallow and a 15 knot breeze has you beating into a 2-3 ft. chop every 15-20 ft.,20 knots you are in 3-4 ft. steep chops. Chop,Chop ,Chop makes for lots of pounding.
You try to Plane at 16 knots will put your Mac.X centerboard thru the trunk beating to windward.
It's all about were you sail and conditions. I can only do planeing speeds 5% of the time out on the Gulf and 60% in the Intercoastal Waterway.
Dave

Sure I can do 15 knots but I rarely am able to go that fast without inciting violence from the crew getting soaked by the spray.
Unless the wind is coming from the right direction, you are not going to be going all that fast, without foul weather gear on.
Jim

i agree with the wind, the spray, and the waves creating a wet & bumpy ride.

i was on the water (the Pacific Ocean) all weekend and was not able to exceed 17 knots under power due to the wind and waves.

that said, i truly enjoy having the extra "horses" so that i can cruise at planing speed and yet only requiring 2/3 to 3/4 throttle.
at 17 knots i consistently travel over 20 miles on a 6 gallons (3.5+ mpg).

Bob T.
"DāBob"
'02X w/ '04 90-TLDI (14" x 11 pitch)
Dinghy Motor: '06 2.5-Suzuki

[delevi]

What I find disheartening is the small return for the extra horsepower, especially considering the cost of that horsepower.
for example:
My Etec 50 will max out around 16 kts (18.5 mph) no ballast, though I've gone a few knots faster with favorble tide.
Crusing speed would be 13 knots (3/4 throttle.)

Bump that up to a 90 HP Suzuki/Merc/Etec/Tohatsu and we're talking about 24 knots max and 18-20 knots cruise.
That really is a relatively small gain considering that horsepower is nearly doubled.

How much more with a 125? The Merc site has tests for the 115, not 125. The 115 pushed a pontoon boat to 29 mph max. That's about 25 knots for a boat weighing about 700 lbs less than an unballasted Mac Not sure if this is totally apples to oranges, but clearly the principle of diminishing returns applies. I would venture to guess that a Mac would benefit much more from a large outboard than an Blue Water Yachts stated at one time that they saw virtually no difference between an with a 70 HP and 90 HP. Maybe there is some merit to this. If this is the case, the new Yamaha 70 (4-stroke) is looking very nice. Looks slim like the Etecs and weighs 265 lbs. Amazing really for 4S at that weight and 70 HP.

[mallardjusted]

Delevi: the new Yamaha 70 (4-stroke) is looking very nice. Looks slim like the Etecs and weighs 265 lbs. Amazing really for 4S at that weight and 70 HP.

Yes, I'm keeping a spreadsheet with specs on a possible 70-90 HP replacement for my Suzie 50. That new Yammie 70 sure looks good on paper!!!!!

[delevi]

I wonder how it would compare to a 70 HP 2-stroke. Weird thing about these modern engines is the huge spread in horsepower with engines using identical blocks. The enigne that Beene posted to begin this thread is a prime example. It is the identical enigne used int he 75/90/115/125 HP. 50-horse power spread with nothing but computer tuning to distinguish them. I wouldn't want to be the guy who got the 75 (lugging around those 50 horses which are computer locked.) Not sure I would want to be the guy buying the 125 either which may be a true 90 with lots of fancy up-tuning. Maybe I have this all wrong. Perhaps some mechanically minded folks can enlighten. How in the world do you lock down a 125 hp and limit it to 75? Can't be just a rev limiter since all you would have to do to work around that is overprop. I know Beene's 75 hp Merc is a beast and will smoke some 90hp enignes out there. So I guess my three questions are:
1. What's the real deal with horsepower? Does it really matter what the number the manufacturer puts on the sticker or are we really looking at CCs?
2. Will a an X-HP modern 2-stroke make the Mac go faster than the same x-HP 4-stroke? Twice the power cycles=twice the torque (in theory.) How about real life application?
3. Where do you draw the line with power? At some point, I would think the Mac (especially the M) would max out. You can take a displacement boat with massive engine and will never get the benefit of that power. The Mac is somewhat different because it semi-planes, but not full plane like a true powerboat, so where does any additional hoersepower become wasted? More than 90? More than 125?

Leon

[Highlander]

Leon

Its more than just the computers , it also involves injector recalibration , sensor changes and maybe even changing flywheels and exhaust porting some of these can be recalibrated to a certain point ! my experience with two stokes is high torq with high HP and high RPM with light load is good !! but this also requires high speed
But with a mac power sailor you require high torq at low rpm for max cruise speed & fuel economy this option will also give you better high speed with a fully loaded boat
my F/S Merc 75 has an even bigger C/C block Than beene's & is fuel injected to boot with even more torq !!
H/P does not me a diddly Sh_T if the torq range is only in the higher RPM OK for a speedy lightly loaded bass boat !
An eng with less H/P & lots of more Torq will lift your boat right out of the water & opperate with more torq & less rpm's for better fuel economy because that puppy is just purring rather than a high H/P eng with less torq thats lugging its butt off until it reaches its higher rpm range before the torq range kicks in , in my opinion this is where the 4/ strokes have an advantage spec . with the Mac M hull with its 17 degree hull dead rise "Semi V Hull " not a flat bottom hull like the mac X

J

[Duane Dunn, Allegro]

I have the all parts to make my Tohatsu TLDI either a 70 or a 90. There are only two differences, the computer module and all it's associated internal programing, and the air intake. The 70hp intake has a plate in it that restricts the volume of air that can pass through. Other than that every part in the motor is identical.

[Bobby T.-26X #4767]

What I find disheartening is the small return for the extra horsepower, especially considering the cost of that horsepower.
for example:
My Etec 50 will max out around 16 kts (18.5 mph) no ballast, though I've gone a few knots faster with favorble tide.
Crusing speed would be 13 knots (3/4 throttle.)

Bump that up to a 90 HP Suzuki/Merc/Etec/Tohatsu and we're talking about 24 knots max and 18-20 knots cruise.
That really is a relatively small gain considering that horsepower is nearly doubled.

you need to take into consideration that to get to a decent speed w/ your 50hp, you must run at or near WOT.
with a 90hp, the motor runs quieter & cooler, and i feel much more relaxed.
basically, it's "peace of mind".

also...when you speak of return, look at the cost difference as well:
- my new '02 Suzuki 50 was $6500 installed in '02
- my new '04 Tohatsu 90 was $7200 installed in '04
and now, most new outboards come with a 6 year warranty.

finally, for those with kids who want to do ski's, boards, and blow-ups...it's essential that you get to 24 knots.

Bob T.
"DāBob"
'02X w/ '04 90-TLDI (14" x 11 pitch)
Dinghy Motor: '06 2.5-Suzuki

[bscott]

There is no replacement for displacement. A larger displacement 4S will have a greater stroke than its bore which will give greater torque at lower RPM than an over bore smaller displacement engine of equal HP (same number of cylinders). The advantage of a bigger stroke is its ability to hold RPM at a lower RPM--thus a good cruising engine. The smaller cc engine will require more RPM to reach its max HP, a better high speed engine. When comparing same HP engines you must also take note of the number of cylinders which will change everything stated above Many different opinions as to which is better, 3 vs 4 cylinders.

AS far as 2S vs. 4S, the 2S engine has less internal mass and friction and will accelerate to WFO quicker. So it will get to its max torque sooner which should get the boat on plane sooner. I believe that once a boat is on plane the engine's computor will determine fuel economy.

Different strokes for different folks.

Leon, your E-tec 50 is identical to the 60 with the exception of a computer flash and an exhaust valve flapper and probably a prop choice. Possibly port timing change.

Bob

[Hardcrab]

Just to add a data point about engines/seats.
My 90 Tohatsu does hit the seat on my M when raised, but it's almost all the way out of the water.
Only the lower skeg is about 1" under, no big deal at all.

As a matter of totally usless fact, I was playing with it on a lazy dead downwind sail about 1 mile back to the slip last weekend.
Straight run, protected water in the breakwater.
Main only with hard vang and boom almost over to the stays.

Motor out of the water, 3.8kts, gps.
Motor lowered, in neutral with prop freewheeling, speed dropped to 3.4kts.
Putting it in gear to stop the prop dropped the speed to 3.0kts.
Motor raised back up, speed back to 3.8kts.

Usless, but interesting info for someone, perhaps.

[Kelly Hanson East]

I'm guessing your an ??

Ive done the same experiment on my :maxx: and found no change...your better transom release is probably the best explanation

[Bobby T.-26X #4767]

My 90 Tohatsu does hit the seat on my M when raised, but it's almost all the way out of the water.

when at it's highest point & locked into place...the Tohatsu 90 does not hit the seat back of an



Bob T.
"DāBob"
'02X w/ '04 90-TLDI (14" x 11 pitch)
Dinghy Motor: '06 2.5-Suzuki

[delevi]

Seems that an ideal engine would be 90 HP with displacement around 1200 cc. Unfortunately, the only two that meet the bill without a massive package are the Etec 90 and Tohatsu 90. I heard the Etec clears the seat while, as posted, the Tohatsu is just a tad too tall. I won't consider another Etec. Too bad the Suzis, Mercs & Yammies won't clear. I guess by packing in all those CCs so the same engine can span over a 50 HP range makes them too big (at least for my taste.) Since I don't have the money now, I guess I can wait and hope the right size engine becomes available. Good news is they're just getting smaller.

Leon

[Duane Dunn, Allegro]

From what I understand, an M is better off with a bit more transom angle than is built in to the boat. I wonder if using some transom wedges would move the Tohatsu motor back just far enough to clear the seat. Another option would be a jack plate which would also shift the motor aft and inch or two. Just how much more is needed to clear the seat on a M?

While it may be a bit to tall, the Tohatsu 90 is a very narrow motor compared to all the 4 strokes and would give you more room around it on the narrow M transom.

[beene]

There are many options available to fix the seat thing Leon.

Raise the seat height using spacers under the hinges etc.
Take the seat out and use something else
Etc

I am no fan of the stoc seat and would not hesitate to modify the crap out of it.

For me, I tilt up til just shy of the seat, lock it up, and forget about it.
Just touches the water at that point.

I know I know....

You want that out of the water......

Buy a 44 footer and give me a call.....

Like that Hunter 460 beside us at Angel Island a few days ago.....

Bet that diesel inboard through hull with a feather prob wont be bothering you one bit.....

LOL

G