Offshoreonly.com - mirage diffuser / rev 4 diffuser

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Quote:

Originally Posted by outonsafari (Post 4717603)

Tested the 27 mirage plus today best ever speed 74.3 best rpm was 4900 (i will have to check that)
it jumps right up on plane and liked alot of trim.

have to watch video seems like it might have pulled 4900ish becacause i remember thinking it needs another 150 rpm.

chinewalk was almost nil, seemed like tab would induce it and more trim it would stop.

i have alot of video to go thru and digest.

the river was calm, glass on last run, ocean was 1& 1/2 feet @ 9 seconds winds under 12 mph

it ran completely different from the 25 mirage plus.

let me get it sorted out but im looking for direction/suggestions

thanks

https://cimg4.ibsrv.net/gimg/www.off...4fedd11962.jpg

https://cimg7.ibsrv.net/gimg/www.off...852ad0caf5.jpg

https://cimg5.ibsrv.net/gimg/www.off...6e65957346.jpg

I would now cut the barrel and have that 150rpm more if lucky. When i cut the barrel of my mirage plus, there was no difference in planning. My propshaft is 5" deep. You can weld the diffuser back if needed.

seems like it runs hi and flat, looks like the inner strakes are just barely getting some water
and it looks like the hull is dry outboard of the outer strakes, to me thats why tab causes chinewalk
(some port tab for torque roll) like it crabwalks and starts the wiggle.
probably way off here but i think move the tabes inboard and set them flat.
i also think the 150-200 rpm the 27 m plus needs will come from sanding the bottom,
it's too easy to send the prop in when there is some little tweaking to do.
besides i'm flush with time and dumb ideas.
any opinions from the guys who really know set up i would greatly appreciate any and all

Sand the bottom with 300 wet and that's it. Lop ⅛ to ¼ off that diffuser and try it again Next step would be going a little less diameter on the prop but keeping the same cup at the end of the blades. Fj for that

The hull is running quite clean. I like the attitude. You slip % is 11. This is quite good.
I believe a diff. mod and the correct Lab recipe will get you to the end goal.
If you can maintain the 11% slip and reach the max rpm with the 27, there wont be anything left on the table. Don't remove diameter from the 27 M+

Brett

Ran another test.
first video shows the camera wasnt mounted square, have to work on that
second video was at 40 mph, trim nuetral. 27 p mirage plus
the battery died before the wot runs.
its interesting to see what goes on back there and hopefully next week ill get some video at wot, looking for any opinion ( anything look right or wrong)

Cool videos Dan. I did similar on mine. Was going to try mounting the camera on a trim tab pointed at the prop to see if that view was any clearer. Might be worth a shot.

Last video was drain plug cam, it has to be turned on before it goes in the water, the remote doesnt work unless its close to it and then you cant see if its recording or not.
I will get clean wot video of the drive one way or another, i believe its gonna point me or more likely someone who really knows setup in the right direction. (already got advice and that will get tested in the next few weeks)

a cushion clamp frankenstein thing may be in order to get the camera out on the tab or its cylinder

https://cimg2.ibsrv.net/gimg/www.off...efb844c53a.jpg

The go pro adhesive mounts are cheap on amazonalamadingdong. I stuck one in the notch on my Baja right above the drain plug and she held on. Matter of fact it’s still on there.

https://cimg7.ibsrv.net/gimg/www.off...1a3892db2.jpeg