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himmelrr.
I have a 2008 p2 with 200 Hpdi and recently put three 100ah lithium batteries in to replace my 3 group 31 agm. I dropped about 120lbs out of the back of boat and naively thought I would gain speed. I was running 69-70 at 5800 rpm days before pretty much no matter what the load and now can only hit 5600rpm. Top end is very temperamental now depending on load…some days 66-67 is about all will do and others I can hit 68. I tried lowering the motor a bit on slide master and redistribute tackle but did not seem to help much. I’m currently running a prop that just says 25m. Not sure what brand. My questions are 1) you think a hydraulic jack plate and different prop will allow me to hit prior speeds or better2) what props seem to run well on p2s? I just can’t see how dropping that much weight cannot be a plus if you get rigged up right. But Just don’t want to go down rabbit hole if not likely to help a good bit on top end.
Interesting I would have thought they would have helped as well to pick up a little speed, I wonder if the center of gravity has moved forward with the loss of weight not allowing the bow to rise as much. Would think lowering engine would help with leverage, but maybe the increased drag is offsetting. Is the amount of trim angle you’re using at WOT same?
You took 120 pounds out of the BACK or your boat. Think a minute. What is that telling you to do.
Yeah I get it…I know I could put weight back in the back and get back where I was but that kind of defeats a big part of why I got lithium’s in the first place. I hoped for more top end. Kind of dumb to throw dumbbells back in the boat if I don’t have to. I have shifted as much tackle, etc as possible to the back and I lowered the motor to about 3.75 below pad to get more lift. I feel like I get now lift now but it’s like the boat stalls on speed at about 5200 – 5300 rpms. I probably only gain 2mph from 5300 to 5600 and I cannot exceed those Rpms before motor starts to blow out and lose speed. And it’s extremely sensitive to differing weight loads from day to day on top end. Holeshot is way better than with previous setup though. I can actually see on the boat water line where it drafts an inch or so less now. A p2 is not big boat for three 100ah agms for 36v tm plus another starting battery so I assumed shedding weight would be ticket but I was wrong.
I guess main question here is do you think hydraulic plate and correct prop will get me where I want to go or am I wasting time. All I’m trying to do is have everything running efficiently as possible and it’s definitely not there right now. Also cautionary tale for those thinking lithium’s will equal more speed in all situations.
Have you tried it with water in the livewells? I’ve had lithiums in a Lynx and now the Cougar 203, I wouldn’t go back to lead acid or AGMs, lithiums improved both mine. Are you running in the same conditions you ran before, could it be a summer / heat issue making the difference?
It could be engine height and that is determined by the steering wheel torque. If you have torque then you lower the engine until it’s minimal pull to the right, requiring you to hold left. If you don’t have torque, then raise it a little until you have a minimal amount pulling right, again requiring you to hold left.
Basically same running conditions as far as temp, etc. Boat used to run 69-70 no matter what. First thing in morning with full tank, empty tank end of day, full live wells, empty live wells, biggun passengers, little kids. 69-70 all the time at 5800 rpm. Boat would just barely kick a rooster tail when running at optimal height. Fastest boat ever ran was 74 when I first got it in 2012 with 28 hrs on motor. I had it stripped down one day with no trolling motor when I was swapping the tm out. But, after putting power poles on, tackle, 36 volt tm, etc it dropped to the 69-70. I was actually concerned I had too much weight in the back as I don’t see many p2 running 36 tm with three big batteries and power poles. Now speed is all over the place depending on all the factors you all have mentioned like full/empty live wells, etc. worst performance is 66 at 5600 and best is 68 at 5600. And motor seems to be throwing much higher rooster tail to hit 5600
I figured swapping to lithium’s would get me back to 72ish. I think I’m gonna bite bullet and get hydraulic jackplate as i could use it a bunch for the way I fish anyhow. I’d like to try another prop someday if y’all have any suggestions.
Play with height and steering torque before investing in more widgets.
Sounds like the boat is struggling to lift as well with the center of gravity shifted forward with less weight in the back and your rooster tail being higher from trimming more to compensate. I don’t know anything about Yamaha props, so can’t comment on them. Did you try emptying out the front compartments and running it just to see if that improves things by chance?
Changing the balance of the boat by that much means you have to go through the whole set up process again. You just made the nose quite a bit heavier relatively. Move the heavier in the front compartments to the rear of the front compartments or to the rear compartments. You may need a different prop and certainly you will need to change the engine height.
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