268 Islander performance questions.

[ElMar]

How does the 268 Islander perform with a single 250hp OX66?

Seems that is common power as well as twin 150s.

I had a Parker 2530 with twin F200s that I thought was a little over powered.

Single 250 ok on this hull?

 

[wahoo33417]

ElMar. If OCNSLR doesn’t reply to your post shortly, do a search of his posts of the same topic. He has answered this question many times - although I believe his boat is an Islander 270. He started out with a single engine on his boat then went to twins, so his is a good case study in the pros and cons of each.

Rob

 

[ocnslr]

Yes, I have answered this numerous times, as well as many lengthy follow up phone conversations.

Do some searching and reading, and if you still have questions pm me.

Not answering here as you didn't provide any information re intended use, operwtional loading, or performance needs/expectations.

 

[Toothpick 10]

I bought a 2002, 270 Islander with a single 250 hp OX66 this past June. I really like the layout of the boat and the ride of the hull. I have researched the same question that you asked.
Most folks will report a WOT speed of about 33 to 34 mph. My WOT rpm of 5,500 rpm produces a speed of 32 to 33 mph.
To reach a cruise speed or 24 to 25 requires about 4,700 rpm. My prop slip numbers are off-the-charts bad.
OCNSLR had poor values also and got some improvement by going with a 4-blade prop. I'm going to do some additional research in the off-season
because it just seems that 250 hp should be able to push a 7,500 lb boat faster than 33 mph.

 

[ElMar]

Yes, I have answered this numerous times, as well as many lengthy follow up phone conversations.

Do some searching and reading, and if you still have questions pm me.

Not answering here as you didn't provide any information re intended use, operwtional loading, or performance needs/expectations.

Any links to specific threads to help me out a little?

Needs and expectations? It’s a boat.

For us basically going to be a third boat in the fleet for mostly inshore fishing and island hoping with the occasional run to Montauk and maybe a little shark fishing. Anything more than that we use the 43 Tiara. Load probably 2-4 people fishing, day tripping.

Main reason I’m interested is our house has a dock on tidal creek but access is limited due to a bridge. The Islander looks like a good boat to check off a lot of boxes for a small day tripper. Without the hardtop of course for me.

I would say good candidte for repower, maybe 300 or 350 Suzuki.
The new douprop is cool but $$$$$

Found a 268 with Bimini and no pulpit so that should help on weight savings.

 

[wahoo33417]

I may be speaking out of turn here, but... Best way to get to a link you're looking for is to click 'search', 'advanced' and then enter '268' (or 270) and 'twins' (separated by a coma) in the topic and 'ocnslr' in the author. That way you'll get the full breadth of the info since each response was tailored to a little bit different question.

Pasted below is just one of the first responses I came across.


Not a direct comparison, but I'll provide some input anyway.

We purchased our 2002 Islander 270 new with a single 250HP OX66. Boat is rated at 500HP (more than the 268), and the 50% HP was marginal. We could cruise comfortably at 22-25kts, and top speed was just over 30knts, but the engine was working hard and fuel efficiency was poor. The other configuration in 2002 was twin F225s, but we purchased the boat show boat already rigged.

We repowered in late 2005 to twin F150s. We gained five knots on our 'comfortable' cruise speed, with 35-40% better fuel efficiency even at the higher speed. And top speed increased to just over 37kts. We now have over 1115hrs on the twins, with many trips 75nm offshore to the Norfolk Canyon area. With five persons, full fishing gear, full fuel and water, 250# of ice, etc, we generally get about 1.5nm/gal.

The 268 has a different configuration aft, with the bottom running surface ending further forward. This affects the HP rating, and the overall ride and performance a bit.

IMHO, a good pair of 150HP Yamaha 2-strokes is a good match for the boat. I would look into the fuel use if those are carbed engines, and determine if the boat's range with the burnable fuel carried will meet your needs. Our boat has a single 150gal tank, and the 1995 model 268 had a 134gal main tank - with a 71gal auxiliary tank as an option.

 

[ElMar]

Not at all, appreciate the help.

I frequent a lot of forums, they are all brand specific. So someone who has been around can usually point a new guy in the right direction without too much searching around and reading.

I would do the same if someone asked a question on another forum I was on.

Thanks.

 

[ocnslr]

Any links to specific threads to help me out a little?

Best way to get to a link you're looking for is to click 'search', 'advanced' and then enter '268' (or 270) and 'twins' (separated by a coma) in the topic and 'ocnslr' in the author. That way you'll get the full breadth of the info since each response was tailored to a little bit different question.

And the results are: Search as suggested

 

[ElMar]

Perfect. Thanks.

 

[Ky Grady]

I'm only a single F225 on a smaller boat, 228, but I benefited extremely well from a re-prop to a 4 blade from PropGods. Give Ken a call and pick his brain on ideas of props. Might be what you need to get the most out of your setup.

 

[ocnslr]

I'm only a single F225 on a smaller boat, 228, but I benefited extremely well from a re-prop to a 4 blade from PropGods. Give Ken a call and pick his brain on ideas of props. Might be what you need to get the most out of your setup.

When we had the single 250HP OX66 I worked with a local prop shop in Chesapeake, VA. Tried a number of different props and found the best overall to be a PowerTech OFS4 x 17" pitch. We were running the 3-blade Yamaha SWS prop, but could still go to the 4-blade without reducing pitch. Strong engine.