Currently running a ranger r 81 vs w a 2000 johnson 175 no jackplate and a 13.5 x 25 renegade at 6000 rpm wot. Gps is at 53 with full tournament load 2 people. Very little bow lift, large roostertail. Thinking of going to a 4 inch jackplate and a 14.5 x 24 raker. Any ideas? Like to get her to 60 fully loaded. What setups and speeds are you guys running. Any help would be appreciated.
6" manual jackplate with a 25" worked Tempest Plus on a Merc 175 EFI. Set at 3 1/4" below pad. 5950 rpms tourney load 64.5 GPS. By myself 66.7 GPS
Ranger R81VS, Mercury 175EFI w/ 25 Tempest
Did you install jackplate if so what gains did you see , ive tead with the vs some say a 6inch is too much with the vs setback already built in ..your opinion?
Put the 6" on it and run the raker.
6" is what you want. Performance gains was pretty substantial. Plate gives the prop more leverage to lift the boat. Also its way better in rough water. I installed it myself and it was pretty easy
Ranger R81VS, Mercury 175EFI w/ 25 Tempest
Did you notice more bow lift, with the jackplate? Think gonna go with 6 " 24 raker set it 3.5 below pad and start there. Hoping the raker will give little more bow lift over the renegade. I installed one on my nitro years ago, pretty simple.
Definitely more bow lift. Then when the prop was worked it has more stern lift as well. Carries the whole boat on the pad much better.
Ranger R81VS, Mercury 175EFI w/ 25 Tempest
I have an R81 w/ mercury 175. I had the same issues. I added a 4" Vance Manufacturing manual jackplate and it solved all my issues. I run a 25 tempest plus prop and have the jack plate set to 3 1/4" below pad. My numbers are just about identical as turfy.
I went with a 6 inch manual jack plate on my R91 and gained a couple mph and got more bow lift and a lot better handling
Forrestercb. Any reason for going with a 4 inch over the 6 inch. What were youruniing for speed before and after.
I chose the 4" because the R81 already has a set back built into the hull. I also have talon sandwich brackets that are about 1" also. So total engine setback is 5". I read somewhere that you dont want to go over a 6" jackplate. My prop to pad height was over 5" so I really just needed to have the ability to raise the motor. I was running in the 55-58 range, RPMS around 5200. The boat had little bow lift, felt like I was riding in a pontoon boat. It was night and day difference, I dont think you'll see much difference between the 4" and 6". My numbers are 65-66 MPH @ 5900 RPM full tourny load, full gas by myself, 63-64 MPH with a partner and his gear. Jackplate set to 3 1/4" below pad.
kandk you have so much prop slip now that anything you do will probably improve your boat. Just putting the raker on and dropping your motor one hole would probably make it faster. You have to remember your running Johnson motor and they need to run deeper than a mercury so 3 3/4" to 4 1/4" under is probably where you'll end up setting the motor not 3 1/4" under.
Mdtrin21 so a good starting point would be 4" ? why do the johnsons have to run deeper . Really think ive got prop slip ? What makes you think that .
Because the slip calculator says so. 33% slip at 6000 rpms. With your motor you should be getting 65-66 with the gade. The older Johnsons and Evinrudes tend to run deeper than a mercury or yamaha. Your probably set too high now with all the slip, a high rooster tail, no bow lift and no speed. Check your prop to pad measurement. http://www.bbcboards.net/champion-bo...ne-harper.html
Ok so i dropped her down 1 hole put on a 24 raker and now she is slipping trying to get on plane ( gotta feather it as to not overrev) and on top end turning 6000 still and speed still gps 52 53. Throwing big roostertail trimmed out water pressure 20 at wot. You think drop it down all the way? Please help still havent gotten the jackplate but thinking i should be st least 10 mph faster according to what everyones saying.
Check this link out. There are several setups like yours and all have jackplates. SetupsLibrary10
Drop it down some more. A jackplate makes this way easier and makes the boat run better. You need to get the propshaft around 3.25 inches below the padOriginally Posted by kandkkustomzhydrographics
Ranger R81VS, Mercury 175EFI w/ 25 Tempest
Enough of the trial and error. Leave the boat as is until you put the 6" jackplate on, set propshaft height to 3 3/4", and get a known, good, 24" Raker prop. Write your starting measurements down then adjust up or down 1/4" at a time as needed.
Well said
2002 Pathfinder 2200V 150 Yamaha HPDI
Ok I put the 6 inch plate on set prop at 3.5 below pad put a 24" raker on prop blows out when trying to get on plane and could not trim high enough without cavitation high rooster tail. water pressure was at 20 psi best speed was only 51 and that was at 4800 rpm going to drob it down all the way to 4.5 below and try it there what do you all think. gotta be able to trim up to 5800 or so without caviitation. just slipping not going anywhere at full trim would crank to 6200 if let it.
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