Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Dauntless 160 115 proxs CT prop testing+?'s
Posted by pinebaron on 07/31/21 - 6:33 AM
#1
Hello whaler central. I have a recent repower 2004 Dauntless 160 2020 115 proxs command thrust.Trim tabs. Just hit 50hrs.Trouble free.Runs Perfect.Wawa 93 octane only fuel i have used so far
Black max 14x19
Engine mount=bottom holes
3 peps+equip.=650lbs
35gal. gas(45gal tank)
WOT 39mph@6000rpm (garmin gps)
Thunderbolt(mirage?) 15.8x21
Engine mount 1 hole up now(1 1/2'' measure above keel)
1 person+equip 300lbs
35 gal gas
WOT 40mph@5350rpm
Vengence 14x19
engine mount 1 up
1 person +equip.300lbs
30 gal gas
WOT 42.9@6300
Laser 2 14x19
25 gal gas
1 person +equip. 300lbs
1 hole up
Cruise 23mph@4200rpm
WOT 44mph(gps)@6070rpm (mercmonitor stored max rpm @6070 and paddle wheel speed @45.4)
I own the black max prop from new and the laser i bought used-could have been worked on?The others i borrowed so they could have been modified .Max rpm is 6300 for my engine would like it close as possible to that.The Only cruise info i have is on the laser.Was trimmed out on all except maybe the black max -my friend was skipping the boat hes a better cap than me though. and i was watching the gauges.
Question is would you stick with the laser or buy something else?The vengence is right on with the rpm.
Out of props to test....was thinking of buying a enertia 14X19 .Mirage 15?x19 15?18 might be good too? Vengence? The other forum has a post of a dauntless 160 merc 115 CT 13.8x21 enertia WOT 43mph@5700rpm one hole up. RPM too low for my liking.
Edited by pinebaron on 07/31/21 - 6:39 AM
Posted by Phil T on 07/31/21 - 12:31 PM
#2
Honestly, the props and setup are not quite where you want to be.
Regardless of prop, you want the engine mounted 2 holes up (top bolt in the 3rd hole down from the top) when the top holes are drilled according to the standard BIA pattern of 1-7/8" down from the top of the transom.
As for the engine. Your target WOT rpm's when running solo with a full fuel load and standard gear is 6300 rpm.
Note that the diameter of a prop is set by the gearcase of the engine.
Prop size is not universal so an X by Y prop by Company A is not the same as the same size from Company B. For this reason, we state the make, model and size of the prop.
Once you move the engine up, I would start with the Enertia in a 21" prop because the CT has a 2.38 gear ratio rather than the standard 2.07.
Note - Speed should be measured by GPS only.
Per member/owner testing the Dauntless 160 performs better with a 4 bladed prop and tabs.
Remember - We set the engine height and select the appropriate prop to reach WOT rpm's/speed so that the engine performs well at ALL speeds. It not just about going WOT all the time.
EDITED to correct gear ratio of CT and appropriate prop recommendation.
Edited by Phil T on 07/31/21 - 1:05 PM
Posted by pinebaron on 08/01/21 - 5:23 AM
#3
Thanks Phil,I am running the Laser 2 until i make a move on another prop.You are right about the prop performing well other than WOT.The cruise on the Laser seems like it could be improved- rpm is too high for the speed it feels like.I will try adj on the trim some more next time im out. I have 28% slip @4200.I have 4% @6070. Going up and down some small swells in the bay the rpms roll up and down enough to raise an eyebrow.I have owned quite a few boats over the years and do not recall rpm changes like that on such small swells.Maybe im not on plane all the way?
The cavitation plate is 1 1/2'' above the keel.Level,neutral trim. I used a long strait edge along the bottom of the keel too measure against-.From what i have read here and elsewhere that is where you want to be.I will have to look at it closely while the boat is under way when i get out with someone.It was spraying a bit until it was raised one hole.The dealer was against raising it from lowest holes and installed it bottom hole.My guess is they are concerned with overheating. That could happen if you are not careful with that adjustment
Edited by pinebaron on 08/01/21 - 5:26 AM