75 E-tch

A forum for discussion of how to rig and tune your boat or kicker to achieve the best sailing performance.
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Bobby T.-26X #4767
Captain
Posts: 906
Joined: Mon Jan 05, 2004 10:48 am
Sailboat: MacGregor 26X
Location: Oceanside Harbor, CA

Post by Bobby T.-26X #4767 »

on a Mac, because you're pushing a "waterbago" (as Frank C. says), you must have a prop designed for a Pontoon/Work boat.
this is a "big dog ear" prop with alot of water surface area.

Image

this 14' x 11 pitch Quicksilver pontoon/work prop is on my 90 Tohatsu. notice the size of the ears.
it provides push, max RPMs at WOT, and excellent top end speed (26+mph lightly loaded / 20+ with ballast).
after trying many, this works best for me.

Bob T.
"DaBob"
'02X w/ '04 90-TLDI (14" x 11 pitch)
Dinghy Motor: '06 2.5-Suzuki
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DLT
Admiral
Posts: 1516
Joined: Mon Dec 06, 2004 10:24 am
Location: Kansas City 2005M 40hp ETEC

Post by DLT »

delevi wrote:I spin a 14x13 on my 50 and you're spinning a 14x11 on a 75. Maybe it has someting to do with gear ration. I am just below the optimum RPM, but with a 13.25 x 13 prop, I get the optimum RPM but lower speed. Went back to the 14x13.
Yes, the 75/90 has a lower ratio, thereby spinning the prop faster. I want to say 2.0 (on the 75/90) vs. 2.67 (on the 40/50/60).
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Rich Walton
Chief Steward
Posts: 79
Joined: Mon Jan 05, 2004 1:05 pm
Location: Dana Point CA. 2002 X 75hp E-Tec

Post by Rich Walton »

I am running the 14X11 and getting 24 mph at 5000 rpm with no ballast. and bottom paint. the prop is a evinrude prop. i dont know if it is a pontoon prop or not. I was very pleased to get 24 out of a 75hp. i could go to a 14X12 and do a little better but i dont think i will. when i had the suz 50 i had the 12X9 prop and could get 18 out of it, but to get up on plane was a killer! i jump up on plane now it is so nice. I just pyt my boat in a slip in emeryvill in the SF bay. If any one want to see it or try it out PM me.
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beene
Site Admin
Posts: 2546
Joined: Tue Sep 19, 2006 5:31 pm
Sailboat: MacGregor 26M
Location: Ontario Canada, '07 26M, Merc 75 4s PEGASUS

Post by beene »

I just bought a 14x11 and a 14x13 from iboats. I wont know till the spring which one is best. But I will post results once known.

Can't wait... just got another dump of the white stuff.... every day this week..

Enough already :?
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Robert
First Officer
Posts: 362
Joined: Wed Jan 28, 2004 6:12 pm
Location: NC

Honda new 90 and 75 359lb. outboards

Post by Robert »

These new Honda 90 and 75Hp outboards have 2.33:1 gears, that is very good for pushing a heavy load.
..
Sounds like a great outboard.
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delevi
Admiral
Posts: 2184
Joined: Fri May 06, 2005 1:03 am
Location: San Francisco Catalina 380, former 26M owner
Contact:
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Post by delevi »

Rich,

Good to have another Bay Area sailor here. We should all plan a little trip once the rains let up. Frank C is in Alameda, I'm in SF, you're in Berkeley and there should be one other guy in Half Monn Bay, but haven't seen his posts in a while. I think we have a few guys in the Sac delta area as well. Would be nice to have a little MacSailor trip in the SF Bay, perhaps in March.

Leon
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