Reply
 
Thread Tools Search this Thread
 
Old 12 June 2013, 15:11   #11
Member
 
Locozodiac's Avatar
 
Country: Other
Town: Lima-Peru
Boat name: Nautile
Make: Sea Rider Boats
Length: 4m +
Engine: Tohatsu 18 /30 HP
Join Date: Sep 2007
Posts: 1,706
Some clarifications:

Test 1 is with small upper def plate as to water flow passes slight under which is the sweet height spot for Tohatsu, Merc, Mariner engines as many boaters having splash over transom issues have solved forever.

Test 2 is with raised engine as to water flow passes slightly over anticav plate.

Both water flows are being cut nicely through the edge angle. The speed difference is about 1Knot in straight flat water courses for both tests. Trin angle is same, being a mechanical trim engine.

The rib used for test is a shallow deep V light hull if would have used a 30 HP for same test would achieved more top knots, but with slight speed difference between both settings as both 18 & 30 have same lower leg shape.

On test 2 find that water flow doesn't pass even through plate as on test 1, on left side side has slight more water and bit of air than on right side, that's the spot where it's probably loosing grip and achieving less top speeds.

This test probably doesn't work on other brand engines, a matter to check under trial and error. Usually stay with factory delivered prop as find them delivering near it's max rpm at wot while solo speeding and rpm drop decrease accordingly while adding more mates or weight on rib.

Happy Boating
Attached Thumbnails
Click image for larger version

Name:	Leg Height Myths (2).JPG
Views:	93
Size:	68.2 KB
ID:	81355  
__________________

__________________
Locozodiac is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 11:01.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.