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View Full Version : Honda 4 Stroke 135 or 150 HP for Dominator



Megatop
17-12-2005, 01:02 PM
Have just ordered my Markham Dominator 7000 but have to decide on either 135 or 150 Hondas. Am wondering what the difference in fuel burn would be between the two. They both have the same cubic capacity but the 150 has the VTEC which gives it the extra HP. Any ideas ?

dfox
17-12-2005, 02:10 PM
G-day adrian, spoke to a few blokes about this and for the price difference they recomended to get the vtec and go 150. Maybe spaniard king could give his view? ...foxy

Spaniard_King
17-12-2005, 08:23 PM
Megatop,

The engines are Identical as dfox says except for vtec, but a little voice from a knowlegable source tells me the fuel maps are a little different over 3000rpm. Which is where the difference is felt (over 3000 rpm)

The torque curvs will be the same to 3000 after that the 150 pulls away, which also means they should have the same fuel figures below 3000.

That should give you an idea what will suite you ;)

The 7m domi is a big boat if your gonna take on a load and reasonable sea the 150's would be better. If your just gonna trawl all day the 135's are enough.

cheers

Garry

vertico
17-12-2005, 08:47 PM
vtec would require more fuel as the more aggressive cam lobes kick in

Spaniard_King
17-12-2005, 09:03 PM
vtec cuts in at 4500, hence the fuel map is different above 3000 to accomodate this ;)

Garry

Megatop
18-12-2005, 10:50 AM
Thanks everyone for the feedback. I guess it comes down to what the benefits are by going 150 HP and if I'll ever need them. The extra 3,500 dollars or so could be used in other areas.
A lot of the time will be spent cruizing to and from the offshore reefs at around 30 MPH at 4200 rpm so am wondering if this VTEC thing is of any benefit fuel wise. Top speed is not a priority for me FUEL BURN over the long term IS.
Logic tells me that to maintain these above figures the 150 would not have to work as hard as the 135 thereby using less fuel. That's my logic but could be totally off the mark.
Maybe Honda technical are the ones to speak to but I don't have any contact telephone number for them. Anyone have any numbers to contact ? Surely they must have done some sea trials on boats around the 3,200 kg and have some figures they can feedback to customers.
The last consideration is maybe I should consider the Yamaha 150 which some owners are opting for.
Does anyone know the difference in price between a pair of 150 Yamahas and Hondas and any other possible considerations?
At the end of the day I'm sure both engines will perform to acceptable levels, it then comes back to FUEL BURN.

Adrian

peterbo3
18-12-2005, 11:13 AM
The new Suzuki 150s are coming. About 17K. Entirely different to the 140.

mark221263
19-12-2005, 07:17 AM
From and engineering point of view the vtec should allow the same fuel ecconomy or even a lttle better for the same power output as the engine can adjust cam profiles and timing and be more effiecent. That being said the 150 makes more power because the additional adjustments to cam timing and profile allow it to pull in more air and therefore burn more fuel.
The 150 hp must work harder than the 135hp to get the HP as it's getting the extra power by burning more fuel and therefore internal stresses are higher. The vtec systems also tend to give a much stronger torque curve down low so you might also get better hole shot which is nice, esspecially in a 4 stk.

In a nut shell if boat does not need the extra hp to get satisfactory performance save the move for gismo's like a nice sounder/gps etc as the 150 is also more complicated and could possibly cost more for servicing. Only a ride in similar powered boat will confirm this.

If you have the spare $ then I'd go for the extra hp. It's always easy not to use hp but when you need it it's very hard to find extra if it's not already there.


Cheers Mark

Synergy
19-12-2005, 08:05 AM
Megatop
Have you though about the Suzuki 140 F&B magazine use them on thier camera boat which is a large cat and have done full fuel trials. Would be worth talking to them anyway.
Paul