Re-powering a MacM from 70 HP up

[Octaman]

MacM + 1950cc = HUGE success

Here’s a not so good video of the new Suzuki DF100 in action on the water, on the MacM.

Apologies for the unstable shooting, I was on my own, filming with one hand handling the boat with the other. I guess a not so good video is better than no video. Duration is just under 5 minutes.

I start and stop and go through different rpm stages.

You shall see the speed of the boat and the shape of the afterwake at different rpms. And you will hear what this engine sounds like. Remember this is still ‘break-in’ period so no WOT running. Notice, if you can, how level the boat remains with just a slight bow-up attitude.

There is a sea breeze developing and the boat is going dead into the light wind in unsettled waters with no chop. No water ballast, engine trimmed all the way down (+wedge), lightly loaded, summer gear not on board, very little water and 35 litres of fuel. Boom and mainsail are not hooked on to the mast but are on board below-decks as is the foresail. Two batteries, one anchor plus chain and rope, plus tools, lines, safety gear, galley utensils, ice-box, marine toilet, odds and ends, etc.

The result is truly breathtaking!!! I hope you can sense it through your screen.

Enjoy!

http://s1224.photobucket.com/albums/ee3 ... 00_26M.mp4

Octaman

[Gater Dunn]

I envy
for a second there I thought I heard a sonic boom

[tom clayton]

thanks i hate my brand new df 70 now. is the clearnace the same as your 70 did it swap out without issues? its looks fantastic is that a 4 blade prop? Sorry i really want one alas it would negate my warranty

[beene]

Man that Suzi really tares it up!

Nice and quiet

You can just hear that performance

Roll it on, and she just begs for more

Sweeeeeeeeeeeeeeeeeeeeeeeeeeeeet!!!!!!

Makes me want the Df140 now

Even lighter than the 100/115

How do they do that?????

Gotta love technology

Heck in a few years they will make a 250 that will weigh less than a 50 and fit under the seat.....
tic toc... see ya in a few years

LOL

G

[Highlander]

Excelent work & really nice performance as expected from Suzi they are the only one's who put out a Race Tuned Engine as a Standard option !!!

J

[Octaman]

MacM + 1950cc = HUGE success

Thanks for the positive comments guys

Tom – One engine came off, the other went on – no problems. That is a 3-blade prop in the video. I intend to try a 4-blade in the near future. Warranty? As someone has said on this site, the Mac is bulletproof… so, who cares about the warranty; go for the thrill. It is well worth it!!!

Beene – it ain’t that much lighter you know. 416 lbs vs 410; only 6 lbs difference. That’s around 1.4%. For me, not a decision-influencing factor. The pistons of the 140 are slightly larger in diameter which means the engine block has less metal to accommodate the larger pistons. This creates the small weight difference. Technology; who knows what the future has in store for us.

Highlander – didn’t know this was a race tuned engine but sure sounds like one and I am amazed at the rev response as you push the throttle forward.
So far, so good!!!

Octaman

[Octaman]

MacM + 1950cc = HUGE success

Hi everyone,

I have some numbers for you; Saturday was a windy day – Force 5 – Today, Sunday, was calm. Break-in period nearing its end. I took some readings of Speed Over Ground (SOG) with the handheld GPS. Readings can differ considerably if motoring into the wind or if calm or going downwind. Plus you have to wait for the GPS display to catch up and settle. My GPS is an older model; maybe the more modern ones respond faster.

The table below is an average of the readings of both days. Hope you find them interesting.

rpm - knots - miles
1500 - 5.2 - 6.0
2000 - 6.4 - 7.4
2500 - 7.9 - 9.1
3000 - 10.3 - 11.9
3500 - 13.4 - 15.4
3800 - 15.0 - 17.3
4000 - 15.3 - 17.6
4100 - 15.9 - 18.3
4200 - 16.7 - 19.2
4400 - 17.9 - 20.6
4500 - 18.8 - 21.6
4600 - 19.3 - 22.2
4800 - 20.5 - 23.6
5000 - 21.8 - 25.1
5100 - 22.6 - 26.0

Once again, I have to point out that the increased speed is a secondary benefit of the bigger engine, in my opinion. The primary benefit is the way the boat rises to a plane and slides on the water. The hull rides the surface of the water with greater ease. This has really transformed the boat into a more pleasant craft that responds well to throttle setting changes.
Today I also maxed the throttle for the first time for one second; I got 5.600 rpm! And a great roaring sound from the engine!
With 5.600 rpm, it seems like the prop is perfect. However, I still think it will be worth while trying a 4-blade one day. I think it will be more beneficial to get all that torque out in the lower rev range.
I am also getting good results with regard to fuel consumption. One tank - 25 litres (6.6 gallons) – lasts approximately an hour. But I can see how this can change if you choose to throttle very high revs (> 4900). Or the other way round if you cruise at a modest 3.800 - 4.000 which is a satisfactory planing speed with this engine. I need to experiment more and log experience with the new engine, then time will tell.

Octaman

[ROAD Soldier]

Ok Vic got 31MPH with a Suzuki 90HP on his . So when you beat that let us know.

[Billy]

Yeah, but Vic ran his X naked (no mast, no gear, and an aluminum anchor).

[ROAD Soldier]

Yeah, but Vic ran his X naked (no mast, no gear, and an aluminum anchor).

So now we get the "Paul Harvey Good Day" rest of the story.

[vkmaynard]

Actually the mast was on but not up (see the DF90 video). We had two anchors, one 16 lb Bruce and one 7 lb Fortress, two batteries, all the sailing rigging below, 18 gal of gas, some tools and galley stuff. Just missing the cusions and head filled with water

[pmcco]

dam, now I want one!!! you guys have all the fun. maybe I can tell the wife that if we had one we could out run the next storm.
Patrick

[Octaman]

MacM + 1950cc = HUGE success

Ok Vic got 31MPH with a Suzuki 90HP on his . So when you beat that let us know.

Hey Road Soldier - I can tell you reeeaaaaallly do looooove my Suzi 100, don't ya ?!?!?! Ha, Ha!

Octaman

[Highlander]

Yeah, but Vic ran his X naked (no mast, no gear, and an aluminum anchor).

So now we get the "Paul Harvey Good Day" rest of the story.

An is a flat bottom hull so will be faster with less HP all else being equal !

How ever the 15deg deadraise though it requires more HP will run faster in rough water with less pounding & sail better in following sea's

J

[beene]

Oh boy
Here we go
Can of worms



G