Hi, I have a 2015 150 MONTAUK with the stock engine, Mercury 60-HP.
[Top boat speed is] about 35 [MPH] with just me and light fuel load.
Q1: If [the engine were changed to a] 90-HP, how will [a 150 MONTAUK perform?]
Q2: [What will the] top [boat] speed be [with 90-HP?]
150 Montauk: Speed with 90-HP
Re: 150 Montauk Upgrade
Yes, you’ll go faster with a 90. That’s the ONLY upside I see. Otherwise the resale value drops, and there is too much weight aft. For my money, if I wanted to go faster, I’d get a 170 MONTAUK with a 90-HP.
Re: 150 Montauk Upgrade
Ever since I got a demo ride the year it was introduced, I have thought the Montauk 150 is underpowered. The Montauk 150 weights the same as a classic Montauk 17 of 950 lbs yet has a max hp rating 40hp less.
With a transom weight limit of 305 lbs. I would consider a E-TEC 90 at 320lbs. I would test the added weight in the rear before you do anything.
With 30% more horsepower I would estimate a WOT speed of 45 with a 90hp. How the hull will handle that is a separate question.
With a transom weight limit of 305 lbs. I would consider a E-TEC 90 at 320lbs. I would test the added weight in the rear before you do anything.
With 30% more horsepower I would estimate a WOT speed of 45 with a 90hp. How the hull will handle that is a separate question.
1992 Outrage 17
2019 E-TEC 90
2018 LoadRite 18280096VT
Member since 2003
2019 E-TEC 90
2018 LoadRite 18280096VT
Member since 2003
Re: 150 Montauk Upgrade
Boat speed for moderate V-hull boats is proportional to horsepower to the 0.5 exponent.
If power increases to 90 from 60, then speed would increase by
( 90/60 )^0.5 = 1.22
If the boat speed were “about 35” with the 60-HP, then with the 90-HP the boat speed should increase to
35 x 1.22 = “about 42”
This assumes no weight increase. Any increase in weight reduces the boat speed.
If power increases to 90 from 60, then speed would increase by
( 90/60 )^0.5 = 1.22
If the boat speed were “about 35” with the 60-HP, then with the 90-HP the boat speed should increase to
35 x 1.22 = “about 42”
This assumes no weight increase. Any increase in weight reduces the boat speed.
Re: 150 Montauk Upgrade
The hull of any particular boat may not be suitable for operating at unlimited increase in speed. There may be a good reason that Boston Whaler limits the horsepower rating of some models differently from other models if analyzed only on a boat weight to power comparisons.
In the particular case of a 150 MONTAUK the weight of a larger engine and the effect of that on overall weight distribution might have been influential.
In the particular case of a 150 MONTAUK the weight of a larger engine and the effect of that on overall weight distribution might have been influential.
Re: 150 Montauk: Speed with 90-HP
I agree with Jim on top speed being around 42. Weight should not be a problem as I have run a heavy engine on a jackplate on a classic 17-footer--which everyone said was too heavy but it ran like a dream. Actually ran smoother than the 130-lbs-lighter setup due to stern weight.
On my 24th Whaler. Currently in the stable: 86 18' Outrage, 81 13' Sport(original owner), 87 11' Sport, 69 Squall(for sale cheap).