Merc DFI to 4s

[peterreb]

Has anyone compared the DFI merc 2/s to 4/s in fuel efficiency and power when getting to the plane when you need it.I,m going to upgrde my boat and an option for me is a 4/s or the DFI?
A couple of mates have told me that the dfi are comparable to the 4s with fuel economy.
Cheers Peter

[craigie]

Peter,

What size engine are you looking at ??

I have a 115 Optimax Mercury (2004 model). Fuel econ is very similar to the Suzi and Yammie 4 Bangers.

If you like, I can post up my fuel figures at various RPM's as a guide ?????

regards
Craigie.

[visarend]

G'Day Peter

I have a 90hp Optimax on my Quintrex 540 Spirit all 2005. Cruising at 25 knots at trip to Moreton from Fisherman Island cost me 32 l of fuel. I also use the boat for skiing and find it pops the skier out witout any hassles. I love the punch of the 2s al low speeds and the economy at higher speeds.

That's my 2c worth

[Trigger]

Have not driven the merc DFI's, but the ETEC is easily comparable to the 4's in fuel economy. The 2's also have a lot more low end punch than the 4's. If you have any doubt about the difference, see if you can get a demo on one.

As a previous 4 stroke owner, I would now never go back to them, and would in fact even put up with a bit more fuel consumption to stick with the grunt of the trusty old 2's. The newer technology 2's are a bonus - the best thing to hit the market from my perspective.

[peterreb]

I'm looking at 5.4 AllyCraft plate C/C with 115DFI merc Optimax or a 5.3 C/C Polycraft with the 115 DFI merc Optimax.
Yes it would be good to see some stats on fuel consumption.
Currently with a Ally bowrider 75 2/s

[craigie]

Peter,

I have just posted a fair bit of info about my Optimax on another Thread.
Have a look at Fishyjoe's post asking about 115 Etech's and Suzukies.

On a normal day heading out from Fisherman's Island at the mouth of the Brissie River, heading across to Tangalooma on Moreton Island, bashing a few beacons for a mackerel, then chase Tuna and Macks North towards Bulwa, I would burn 45 - 50 litres of fuel and cover 100k's.

At Idle speed of 650 revs, the Optimax 115 will burn fuel at .7 of a litre per hour :o, so a day trolling for Flathead & Bass with lures equates to SFA in fuel costs 8-)

On my 5.4m "Cyclone" fibreglass runabout, the 115 Opti will grunt it up on the plane at 3100 revs, burning approx 13 litres per hour, doing 17 knots.
4000 revs gives 24 knots at 19 -20 litres per hour (optimum cruise speed).

WOT gives 39 knots at 5800 revs for a fuel burn of 37 litres per hour.

All the above information (and much much more) is provided on the dash of my boat via the optional Mercury "Smartcraft" gauges. Not cheap, but worth every cent !!

Regards
Craig.

[MADKEEN]

Hi Peter,
We opted for a optimax 90 on a 6m mag seajay last oct and have done 350hours last weekend. On an average day fishing of moreton island we leave out manly and fish the 35's and run around a bit. I've caluted the fuel consumtion quite a number of times and average beteew 2.2km up to 2.5 km a litre depending on how hard we push her. In my opion great motor love the reponse it gives when needed, crossing that bloody bar sometimes.
Have to agree with Craiggie the smartcraft gauges are a most.

David.

[ahoj]

My rig can run on 4 liters all day at full stick @ 14 knotts 6 hp--- some ecconomy......

Ahoj