[SPLASHED] I/O (Sterndrive) Conversion to Outboards

tpenfield

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I ran the boat up to WOT on a couple of occasions today . . .

I probably have not trimmed up enough, as I was only getting 5100 RPM and 48 mph.

Time to plane is about 3 seconds (great improvement) and only needs about 3,000 RPM to come up on plane

I sent some performance data off to the re-power shop for their consideration.
 

tpenfield

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Here is my chart of the speed run yesterday. The Naval Architect had estimated the 'hump speed' of 18 mph (coming on plane) of the hull in its new form using Orca software and the 3D model of the hull. Looks like it was spot on, based on my testing of time-to-plane and planing speed.
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Honda-BF350-Preformance-1.png
 

Scott Danforth

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Ted, did you share the real world test with the NA? they like the feedback.

do the hondas have a limited output like some other motors until they get thru the break-in period? that may explain your lower than expected WOT. or you are slighly over-propped, considering you dont have the bilge full of beer yet.

also, still waiting for the Cheshire like grin
 

tpenfield

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Ted, did you share the real world test with the NA? they like the feedback. I probably will send him a few pics and the data

do the Honda's have a limited output like some other motors until they get thru the break-in period? that may explain your lower than expected WOT. or you are slighly over-propped, considering you dont have the bilge full of beer yet. IDK, it is above my pay grade

also, still waiting for the Cheshire like grin . . . :LOL:
 

tpenfield

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Quick Update. . .

The re-power guy (Mike) said to re-run the speed test with greater amounts of trim. Additionally, he asked if I could get a visual of the lower units at speed to see where the ventilation plates are relative to the water stream.

I have a camera set-up for my trailering, which might do the trick for getting a visual.
 

tphoyt

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Now that I thought about for minute I guess people ask him to do that all day long. He wouldn’t get much done.
 

tpenfield

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If I were Mike I would looking to go for a ride.
Mike [Preservati], (Preservati Marine LLC), most likely will be going for ride when he comes out to do the tuning. He used to be at Millway Marine in Hyannis, and went out on his own in the past few years. They deal with most outboard engine brands, but are a licensed dealer for Honda Marine and Dometic/SeaStar/Optimus systems.
 

redneck joe

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get a visual of the lower units at speed to see where the ventilation plates are relative to the water stream.

I have a camera set-up for my trailering, which might do the trick for getting a visual.
i was wondering, and assuming, height was a wee bit adjustable.
 

tpenfield

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The engines can be moved up a 'bolt-hole' on the clamp mounts . . . not the easiest thing to do though.
 

Pmt133

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Just out of curiosity... which rule of thumb was used to set the initial AV plate height? I know there were a few options and I'm curious (and don't remember because CRS) what the initial height was.
 

tpenfield

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It was about 1-1/2" in total. A balance between 1" per 12" and what made sense from a mounting perspective.
 
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