Jump to content

HP required for an Alan Wright Variant


Guest

Recommended Posts

Hi all

 

I am looking at a possible purchase of a variant and currently have a 2stroke 4hp Yamaha with a standard length shaft. I have two questions, is 4hp enough grunt for cruising the gulf and will I get away with the short shaft or is a long shaft outboard a must?

Link to post
Share on other sites

Kind of depends where you will be motoring. We had a 4 hp long shaft on our family Tasman 20 fin keeler back in the day. it was too small to push us up the Panmure river against the tide and a sou-westerly (read short tack motorsailing instead), but was probably adequate for anything else. Your biggest problem will be keeping the prop in the water when its rough. Get something with the longest shaft you can. For cruising I'd go for an 8hp with a 25" shaft, had one (Tohatsu) on the old Harmonic and it worked really well.

Link to post
Share on other sites

Alan's son Don (Jaws) works with us here at Hallspars and says that they recommend a 6hp longshaft as a minimum, but would recommend an 8hp but many came out with a 9.9hp and that would be ideal for a variant and allow you to motor into anything!

Link to post
Share on other sites

After some readings in crew.org.nz and other websites, I believe the pitch of propeller is more important than getting more power. Many manufacturers provide options for different propeller selections.

 

There's formula for required HP for a yacht. I think 4ft for 1HP. For your case, 6HP engine should be adequate for the use. The smaller engine is lighter and cheaper. Looking at the current price for Yamaha 4 stroke engine, $2.5K for 6HP and $5.5K for 8HP. Massive price difference for extra 2 HP.

 

Check this link for more info:

http://crew.org.nz/forum/viewtopic.php?f=6&t=22360

 

BTW, I am also thinking about getting a outboard for my S&S 24 Falcon. I would go 6HP with smallest pitch propeller with bigger radius.

Link to post
Share on other sites
Looking at the current price for Yamaha 4 stroke engine, $2.5K for 6HP and $5.5K for 8HP. Massive price difference for extra 2 HP

 

Last Yamaha 8hp long-shaft two stroke with hi-thrust prop I bought was NZ$2850 incl GST. That was 18 months ago so they havent gone up that much. It was to replace the previous one that had lasted 20 years, the first 18 of which it had never been washed.

 

Not sure if you meant 4-stroke or not. Just found a new Merc 8hp long shaft and hi thrust prop for $2450 incl GST.

 

Dont mess around, go for a few extra horses, long shaft and hi thrust prop. One day you wont regret it trying to motor out of a bay when the wind and waves pick up.

Link to post
Share on other sites

The prices are for 4 stroke engines. I guess there are split opinions between 4 stroke vs 2 stroke engines. I prefer 4 stroke for clean burning, efficiency, and quietness. I guess it's contradictory on my last comment on "Ligher". Yes they are heavier than HP equivalent 2 stroke engines.

Link to post
Share on other sites

Horsepower to boat size is a pretty academic exercise really. Every boat will meet its match against wind and waves even the wahine did! I learnt a good lesson once trying to motor out of a bay 12hp 28 foot boat couldn't even hold the bow to wind had to "gibe" several times and try again and still couldn't make progress. Gave up eventually ,next morning wind and sea the same so reefed sails and had another go, as BB suggests far better progress.

Link to post
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...