To Jack Plate Or Not To, Need Answers

[Jimmy Easterling]

I have owned this new 5 inch manual jack plate for over a year now and don't know what to do about it. 17'9" Z6 with a 115 Opti, Laser II 20P three blade, GPS at 47 mph. Gets on plane in about 5 seconds and can keep it on plane at about 25 to 27, any slower and it falls over. I would like to pick up, oh, 15 mph or so,, maybe a couple or three. I have never run a boat with a jack plate and don't know what to expect. Will it help with slower, on plane speeds? Will the hole shot be as good or better? Will top end be a little better? And what about stability, better, same, or worse? I have an appointment to get some other stuff done one week from today and need to decide before I take it in. Any and all thoughts would be appreciated. I think these guys get $90 an hour, any idea on what it should cost me?

 

[Scott Hammer TOXIC]

In the JP world that is a small one but it will help holeshot and topend. All of the 9 series come with them standard and there is a reason why!! You will have to re-set up the motor and possibly prop but in the end it will have better performance and there are really no downsides.



TOXIC

 

[TritonGlenn]

Jack Plate will help - but you aren't going to see a 15 mph gain without changing out your engine. Playing around with the setback and getting your prop worked by a professional will normally gain you 3 to 5 mph. Jack Plate by itself might give you an extra MPH or two.



Years ago, I added a 6" Rapid Jack manual to my 18 foot Cajun bass boat / 150 Johnson FastStike. Just that addition picked up another 2 to 3 mph. Prop work was needed to get my RPM's right, and after that I had a blistering hole shot and was up 3 to 4 mph over what I originally started with before adding the Jack Plate. Boat handled like a totally new boat - it didn't feel the same. It was great.



All the best,

Glenn

 

[Jimmy Easterling]

Two things: The RPM easily gets to 58-5900 when trimmed out. And "and getting your prop worked by a professional", does that mean re-engineering the prop I have or changing it for something different? Also, I took the storage bins out of the back, they are full, and holeshot went from 5 seconds to almost 3 to plane, but top end didn't change. I guess I need to redistribute some weight.

 

[TrepMan]

Jimmy - I have a 4.5 inch manual jackplate on my 17ft 700lx with the 115 Carb'd merc (It came with the jackplate when I bought it). The Z6 is rated to a 130hp, so you are about as close as you can get with current Mercury engines as they don't make 125 or 130 HP Optis. Your boat is 9 inches longer and i think wider, but with the 115 Opti I would think with the right setup you should be in the low 50's GPS speed. I have played (and still playing) with the setup on my boat, but I have hit 57mph with a light load on a cold morning, but can push 52-54 all day long.



If you have the $$ and time, as others have said it won't hurt to add the jackplate, I would say (and I am NOT a guru) 6 inches or less setback, and you could post on Bassboatcentral.com for Props suggestions from Mark or Pat Goff, but I would think something in the 23-24p size if you get the motor hieght right will get you more speed. Just make sure the prop has vent holes to help on planing.



And "and getting your prop worked by a professional" means having a prop shop take your existing prop (or what ever prop you end up getting) and having it tailored to your set up (more cup...), its not cheap you are talking $200+ plus the price of a good prop, so i would think you are talking $300 for a new prop, $200 for a prop shop (if you need it), $150 for 6 inch jack plate, $200 for a shop to install (you'll need to see if the current steering cables are long enough).



Just a thought, you could find a local shop that will let you 'try' props and see if moving the motor up and re-proping gets you what you want before you spend the $$/Time on a jackplate.



And if you get one, make sure its adjustable. I have been playing with my setup as i've gotten different props, and its MUCH easier with a manual adjustable plate then having to have 2 guys come over every time you want to change the height to hold the motor while you un-bolt and rebolt the motor! looked on eBay and 6 inch adjustable plates seems to be $150-190

 

[Jimmy Easterling]

Trep, I bought a five inch manual adjustable (CMC) a year ago and just haven't put it on yet. The local boat shop is a Tracker/ Mercury dealer and is a somewhat small business, so it may be possible for them to let me try different props. I am not sure what prop came on this boat, I was getting 47 MPH on guage, at the time I didn't have a GPS, and holeshot really sucked. I took it back to Bass Pro Shop in Savannah, Ga (I tried to get them to install the JP, but they said I didn't need it) and they changed out the prop and everything got better. Even now, my guage says 54 MPH but GPS says 47, which leads me to believe that when my guage, before new prop, was reading 47 I was actually getting in the 42 MPH range. The original advertising for this setup by Tracker was 52-56 MPH.

 

[TrepMan]

Yup, don't ever believe the Speedo, notouriously OVER states the speed. I would expect the 115hp on that boat to not exceed the speed I could get since my boat is smaller/lighter, I would think 52 would be good top end, but will be interested to see what you end up with.

 

[Derek Chance]

I have never seen where a jackplate did not help a situation. except on small rigs.

 

[TritonGlenn]

Trepman,

Oddly enough, smaller / lighter doesn't always equate to faster. I know - it would only make sense. However, I found that if I compare my Triton TR-20X to a TR-21X (my comparisons are with a 2005 model of each), I found that the TR-21X, although a foot longer and approximately 26 pounds heavier, will outrun my TR-20X almost every time if they are rigged with the same engine and approximately the same load. I have no idea why, but I assume the hull design must be slightly different in some other way than just "longer". Either that, or the longer hull just slices through the water easier. I don't know.



When I bought my 2005, my way of thinking was "I can get a foot shorter boat with the same size engine, so it should be faster". Well... I guess I was wrong. The 21X isn't much faster, but if we both take off at the same time, I start to slowly fall behind and I can't seem to ever catch them, no matter what I do or how I'm loaded.



Odd. I know.



All the best,

Glenn

 

[TrepMan]

Maybe you butts bigger then the guy in the 21x!!! LOL

 

[TritonGlenn]

Oh you just had to go and point that out, didn't ya' Trep. :lol::lol::lol:



I've driven them both, and the 21 just kept outrunning my 20. I've known other people that say the same thing about those two boats.



All the best,

Glenn

 

[Jimmy Easterling]

OK, I am having the jack plate installed and when I put it on the water I will have no idea how to adjust. The only thing I know is small adjustments. What, other than slower speed, is an indication that I am going the correct direction and what is the indication that I have gone too high? Not airborn, I hope.

 

[Scott Hammer TOXIC]

If you are too high your water pressure will drop. A manual jackplate will require you runnung, then taking the bolts out on the slide and cranking the center adjusting bolt. Leastwise that is how it is on my JP. I've never had to mess with the setup on mine. I feel very lucky to have a big heavy 929 that runs 67 all day long loaded up like a tackle store!! Somebody needs to give her a new home!!:lol:



TOXIC