View Full Version : Best SS prop for 115 MERC EFI on 2008 1750 Lund Fisherman
mdoehling
10-28-2008, 10:34 PM
Looking to get a SS prop for my Fisherman this winter. just purchased at the end of sept. and want to have it ready to go come next April. Any thoughts...
mdoehling
The right prop for your boat depends on your load and being you are running a four stroke with a small gear case Mercury does not make a lot of performance props the your application. A Lazer II, Trophy or a Vengeance would probably be you best bet. The Lazer is a three blade and the Trophy is a four blade. The Vengeance is a copy of a Black max in a stainless steel but has much better performance. Also Look at Power Tech, they make a lot of performance propellers for small gear case motors.
propmann
10-29-2008, 09:36 PM
Powertech has the best mid size props out their. The RXB4 is a great prop or the NRS3, It depends on what your doing with your boat, and the weight your going to have. If you need some advice about powertech props we can help you out. 218-824-0000
tfranjesh
10-29-2008, 10:04 PM
I have exactly the same boat with the same motor. I have a 18 pitch Mercury Vengence. I can get close to 46 MPH by myself and 41.5 with 4 guys. When I have a heavy load it takes a while to get on plane. This prop performs great but, with a heavy load I feel that I should have a 17 pitch due to the slow planing time. It does jump right up on plane with a moderate load though.
Tom Franjesh
Tom,
What RPM are you turning by yourself and with the 4 people at WOT?
fxnrxn
10-30-2008, 02:05 PM
I'm running the same rig, and I'm turning a Turbo 13.25X17 3 blade with 2 open vents. Hops right up on plane, and does 41.9 GPS at about 5600 RPM. Idled down, can troll at about 1.3 mph, dead calm, about 1.6 mph. I would love to try a 18 vengence, but up here in windy Sakakawea Country, there just aren't many calm days, and WOT just isn't that common for me. The 'hole shot' is more relevant. Mike
fsh4eye
10-30-2008, 03:04 PM
Mdoehling
Same motor that I have. Mine is a 2007 model. My motor has a max RPM of 6400, with a Max RPM range of 5800 - 6400.
Some one will have to help me out on this but do the older 115 merc 4 strokes like 2004 or so have a lower max rpm?? Not sure if the gear box is a different ratio on these or not if they do have a different max rpm. Not sure why mec changed this if this is even true for sure. I have a friend that used to have a 03 17’ fisherman with a 03 115 4 stroke merc. And I remember him telling me that his max rpm was 5800. His motor was allot shorter then my 07. Can some of clarify this?
Only reason I am saying this is because if you compare the performance from one of the older motors if they indeed do have a lower max rpm you may have to go down another size in prop to get your max rpm in the upper range of the motor specs so you are not lugging the motor.
tfranjesh
10-30-2008, 03:14 PM
If I'm remebering right I'm at 5,900 RPM's light and 5,600 with 4 of us. I don't get to many opportunities to run full speed because I mainly fish Lake Erie. I'm going out on Tuesday with 4 guys so I will check the RPM's and get back to you. My speeds were off the GPS utilizing the max speed feature. Honestly, I should probably be running a 17 pitch too due to the water I fish and the amount of people I fish with.
Tom
San Chan
10-30-2008, 06:08 PM
Mdoehling
Same motor that I have. Mine is a 2007 model. My motor has a max RPM of 6400, with a Max RPM range of 5800 - 6400.
Some one will have to help me out on this but do the older 115 merc 4 strokes like 2004 or so have a lower max rpm?? Not sure if the gear box is a different ratio on these or not if they do have a different max rpm. Not sure why mec changed this if this is even true for sure. I have a friend that used to have a 03 17’ fisherman with a 03 115 4 stroke merc. And I remember him telling me that his max rpm was 5800. His motor was allot shorter then my 07. Can some of clarify this?
Only reason I am saying this is because if you compare the performance from one of the older motors if they indeed do have a lower max rpm you may have to go down another size in prop to get your max rpm in the upper range of the motor specs so you are not lugging the motor.
Stated in the 2007 Mercury Catalog;
90EFI Full Throttle 5000-6000 RPM
In-Line 4 ~ 1732cc
3.23" X 3.23"
In 2006 Catalog;
90EFI Full Throttle 5000-6000 RPM
In-Line 4 ~ 1596cc
3.11"X 3.20"
There are several places that will let you try out props before you buy md. I'm not sure of the weight of that boat but I run a 17 balistic.That prop works well on my boat and it was cheap.I would be more apt to look at a turbo, stiletto or a power tech as propman suggested. I have heard from several people that the Vengeance prop is a step up from Aluminum and not much performance as the other props mentioned plus it costs more.
Keep in mind that even though you don't run wide open throttle you must be at the top end of the Operating range(5800-6400) to get the most efficiencies and performance out of the motor.Lower than operating range will lug the motor and have effect on the motors longevity.
Do not overlook engine height either.Run the boat and see where the AV plate is running. it should be splashing the top of the plate.More motor in the water is more drag and robs performance. Make sure if you raise you are still getting water pressure.
I'm no pro at this but this is what I did with my boat and am pleased with it. Good luck and have fun with it.