Optimax improvements prop, rpm, gph

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Jaysen
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Re: Optimax improvements prop, rpm, gph

Post by Jaysen »

Yes. He collecting better numbers on current performance when he can. One of the mistakes made was wiping the engine performance display. Once he has that synced again data collection should be easier.

I told him that “the only way to get good fuel consumption is to fish on someone else’s boat”.
My already completed 'Lil Bit'. A Martens Goosen V12 set up to sail me to the fishing holes.
Currently working on making a Helms 24 our coastal cruiser.
“Mark Twain/Samuel Clemens” wrote:Eat a live frog first thing in the morning and nothing worse will happen to you the rest of the day.
Jaysen wrote: Mon Apr 29, 2019 3:44 pm I tried to say something but God thought I was wrong and filled my mouth with saltwater. I kept my pie hole shut after that.

TomW1
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Re: Optimax improvements prop, rpm, gph

Post by TomW1 »

Jaysen here is one thing you can do and that is a speed chart vs. rpm vs. mileage, this will show him where his sweet spot is.

Set up a course 1 mile long and run it both ways and set your rpms for a constant amount. To keep it short start at 3000rpm. Do it it on as calm as day as possible and if wind is present one upwind and one down wind.

RPM's Speed(MPH) GPMile
3000
3200
3400
3600
3800
4000 32 8
4200
4400

I am looking for 3 things here.

Fuel efficiency
Propeller efficiency
Fuel economy

The other thing I absolutely need is the Brand, Name Of and Diameter x 15 pitch of the propeller. The reason for this is if he has a prop that is forcing his bow down instead of stern up he is losing efficiency. There are a lot of nuances in choosing the correcting a prop especially in these smaller boats. :D The info will be on the barrel on in his sales papers. Something like Mercury, Mirage Plus, 15.5 x 15. I hope he has it pulled out of the water. :lol:

Hope you can talk him into doing this.

Regards, Tom
Restored Mirror Dinghy, Bought OD18 built by CL, Westlawn School of Yacht Design courses. LT US Navy 1970-1978

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