Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: 1994 21' Outrage with a 250 E-Tec Performance
Posted by Lucky B on 01/14/14 - 2:00 PM
#1
I have 1994 21' Outrage with a 2012 E-Tec 250 and am running a 21p aluminum prop. I am currenty getting 44mph at 5600 rpm with 3/4 fuel and two guys. Does this seem about right?
I am going to be getting a stainless prop soon and was thinking a 19p or 20p Rebel. I would like to be closer to 50 mph and between 5800-6000 rpm at WOT. What are your thoughts?
(moderator note: changed the abbreviated year to the full 4 digit year as requested on the front page of WhalerCentral.com)
Edited by Tom W Clark on 01/14/14 - 3:25 PM
Posted by Tom W Clark on 01/14/14 - 2:17 PM
#2
Nope. That does not seem right at all. A 2012 E-TEC 250 turning 5600 RPM swinging a 21" pitch propeller should be going a lot faster than 44 MPH.
At 44 MPH the calculated propeller slip is over 26 percent!
5600 RPM is the ideal WOT RPM for that motor so that is good, but the slip tells me that the prop has WAY too much pitch and it is only the lousy grip of the aluminum prop that is allowing the motor to get to its optimal RPM range.
Try a 19" Rebel and see how it does.
Also be sure the motor is mounted three holes up on the transom (as high as it can go).
Posted by Lucky B on 01/14/14 - 5:41 PM
#3
I will also add that it is 30' inch shaft as required by the 30' inch transom and also that there is no T-Top. The engine is mounted in second hole from the top (so I assume that is the second lowest possibility) and based on what you are saying, it should be in the bottom hole. I do not have a picture unfortunately. The dealer has a 19p Rebel I am going to demo. Should I demo the prop before raising the motor?
Posted by Lucky B on 01/14/14 - 5:59 PM
#5
Thank you Joe. My motor is "One hole up".
Posted by Tom W Clark on 01/14/14 - 6:11 PM
#6
You should raise the motor first and try the Rebel.
Posted by tmann45 on 01/15/14 - 10:35 AM
#7
Just for a similar data point, my 1996 21 Outrage with F250 Yamaha 4.2L will run +/-53 MPH turning a 17" Revolution 4 at 6100 RPM. This is running light.
It will do 57 MPH with a 19" Rev4 turning 5700 RPM, again running light.
Posted by Lucky B on 01/15/14 - 12:36 PM
#8
tmann45 wrote:
Just for a similar data point, my 1996 21 Outrage with F250 Yamaha 4.2L will run +/-53 MPH turning a 17" Revolution 4 at 6100 RPM. This is running light.
It will do 57 MPH with a 19" Rev4 turning 5700 RPM, again running light.
Thank you Tmann. Just for comparative purposes, do you have a 30in Transom with a 30in shaft on your Yamaha? Also what hole is it mounted in? Thank you.
Edited by Lucky B on 01/15/14 - 12:37 PM
Posted by duf on 01/15/14 - 12:53 PM
#9
I had a 22 Whaler Center Console with a 225 2006 ETEC and could do slightly over 50 MPH all day long.
Duf
Posted by tmann45 on 01/15/14 - 4:02 PM
#10
Lucky B wrote:
tmann45 wrote:
Just for a similar data point, my 1996 21 Outrage with F250 Yamaha 4.2L will run +/-53 MPH turning a 17" Revolution 4 at 6100 RPM. This is running light.
It will do 57 MPH with a 19" Rev4 turning 5700 RPM, again running light.
Thank you Tmann. Just for comparative purposes, do you have a 30in Transom with a 30in shaft on your Yamaha? Also what hole is it mounted in? Thank you.
No, I have the 25" cutout transom. Motor is mounted all the way up.
Posted by Lucky B on 02/03/14 - 2:26 PM
#11
I raised the motor all the way up and it did help some. It is now in the proper hole as I have no cavitation at turns and it got rid of some turbulent water that was happening at speed when it was two holes down. As for performance, I am still at 44mph WOT. The raising of the motor gave me 200 more RPMs so now I am right at the limit at 5800. From here, I think I need to purchase a 23p Rebel as my 21p Aluminum is created to much RPM. Thoughts?
Posted by Tom W Clark on 02/03/14 - 5:07 PM
#12
A 23" Rebel is w a y too much pitch. Try a 19" Rebel...or any number of other excellent propellers for a boat that size with that power.
Posted by Lucky B on 02/03/14 - 5:31 PM
#13
Tom W Clark wrote:
A 23" Rebel is w a y too much pitch. Try a 19" Rebel...or any number of other excellent propellers for a boat that size with that power.
I am already at max RPM rating of 5800, won't lowering my pitch increase my RPM's too far?
Posted by Tom W Clark on 02/03/14 - 5:38 PM
#14
No, because you are comparing different propeller models. Your aluminum propeller is slipping badly. Calculated propeller slip is 28 percent!
The Rebel is going to yield a calculated propeller slip of around 5 percent and the RPM will fall because of it.
Posted by boatdryver on 02/08/14 - 7:06 AM
#15
Say LuckyB. Just checking....
44 knots=50.6 mph
maybe its just a coincidence, but I wondered if your GPS is set for knots
JimL
Posted by Lucky B on 04/24/14 - 5:24 PM
#16
UPDATE
Got a 19' Rebel and have increased performance. With two guys and full fuel I am seeing 5100 RPM and 48mph. Fuel economy is increased throughout the RPM range and hole shot is awesome. Probably could swing a 17' though.