Prop & Jack Plate ?

[Tyler]

Hello everyone. I have been watching this forum for quite some time now but just registered. Before i ask any questions i would like to thank everyone for such great information that is on this fourm.

Anyway my question(s) is/are i am wanting to get more out of my setup.

My boat is a 2007 Tracker Pro Team 190 TX with a Mercury 2 stroke 90HP.

I have had it out on the water only a handfull of times and i have noticed that it get out of the hole fast and easily but the top speed is 45-46 MPH and there is turbulance/air pocket(s) right behind the boat.

So should i get a jackplate and a prop or just one of them. I would like to see if somehow i could get the boat to hold at least 50 mph or as much as it can put out.

Any input of brands, types and or places to purchase would be greatly appreciated.

Thanks.

[Dutch]

A 19' boat with a 90 is doing pretty good. I know of an 18' with a 115 which could barely maintain 50 mph. If you are running an aluminum prop, you might get a bit more out of steel but the new alums. are pretty good.

[Rick F]

You will get a little more hole shot and top end. 50 is possible. If you can, check out the magazine BWB(Bass and Walleye Boats). They have a ton of info on props and jackplates in 2 or 3 issues last year. With your prop you will need to make sure your are running at or near max rpm's. Your 90 hp should max out at 5800-6000 rpms at WOT if my memory is correct. BWB also had an issue with all motors and their specs. If not then you need to find a prop that will get you there. One thing, are you going off your speedo or GPS? Speedo's can be up to 5-8 mph off. I read an article where this guy added a jackplate and correct prop to his 16 footer with a 60 hp 2-stroke and hits 60 mph. Do your research and ask around or you will waste a lot of time and money for nothing.

[Tyler]

Well guys i appreciate the input. I was tracking my M.P.H via my speedometer that came with the boat. So does anyone have any suggestions to go either the jack plate route or the prop? I really do believe i will go the jack plate route but it will be a manual. Anyone please feel free to chime in. All suggestions are welcome.

Thanks.

[Gary Lange]

You would need to check with Tracker Boats to see if they would recommend a Jackplate on that boat. Just raising the motor up the the next set of holes will get you some more RPM's. It is best to run the motor as close to Max Recommended RPM range as possible for best performance. What Pitch Prop do you have a what is your RPM's at when running wide open? Also what is your Water Pressure? You will need a GPS Speed rather then a Speedometer reading because the Speedometer to way off.

[Yellowbee]

IMHO - there is no need to add a jackplate for your situation except for making it easy raising and/or lowering the motor. An 18' 6" boat with a 90 hp probably won't gain much if anything. The hight of your motor as it relates to best performance is purely dependant on the hull design. From what I can see from the specs at Tracker, you don't want to be running your motor too high expecially with an aluminum prop as the closer to the top of the water the prop runs the more likely you'll begin to have blade stress and possible cracks that can result in throwing a blade - and that's not fun at any speed. Skeeter mentioned a pressure guage - best piece of equipment you can have!! To get a true evaluation of your situation we need to get several bits of information: 1) Motor height in relation to the pad (the pad is the back running surface closest to the transome) - measure the distance between the prop shaft (the tip of the nose cone) and the bottom of the pad. 2) Speed at WOT (wide open throttle) - I think you said 47 3) Prop pitch - I think you said 21 4) water pressure - that will be the hard one for you since you don't have a guage and 5) Your RPM at WOT. With this we can calculate your prop slipage and give you an idea of how high you need your motor set. You also may want to consider contacting your local prop shop - one that customizes props as they may need to adjust your leading or training edges to give you more bow or stern lift depending on your needs. Keep in mind the more of the boat you can get out of the water, the less drag you have and the faster you can go. In my situation, once I'm trimed out at WOT, I'm running on the back 18" of a 21' boat and the prop.

[Rick F]

Sounds like the 4 blade prop helped getting on plane. I found this web site

www.kencook.net/Setupart.html and it gives you a formula for TMS(theoretical max speed) This is suppose to be the top speed of the boat period using this formula doesn't matter hull, weight of boat, etc... When I plugged in your numbers however it didn't add up because I got 44.9 MPH for the speed. You said the GPS read 47 which means you are getting better than 100% effeciency for your boat which is impossible. Maybe my numbers were incorrect but I used 5200 for max rpm, 21 pitch and 2.30/1 gear ratio which according to BWB magazine is what the 90 2 stroke mercs come with (not Opti's though). I would say you are right at the top speed of your boat and buying a jackplate would be a waste of money. You might get 1-2 mph or it could make it worse if that and how often do you run WOT? Keep us posted on your progress and I agree with the above, buy a water pressure gauge and have it installed if you plan on raising your engine even on stock transom.

[Wayne SW/MO]

Is your cavitation plate at the right level?

[wildminnow]

hey calico wayne I think your Jack Plate is at its maximum level

[Wayne SW/MO]

In my experience its hard to get much more in the way of speed from a factory package, but I think Tracker is Conservative in their propping. The reason they do this is because they use the motors on several different hulls, so it may not be the best configuration for yours. In order to get an accurate speed reading you must run on the same water conditions, I.E. light chop, ripple, flat, etc. You'll get your best speed from a planing hull with a light chop usually.

You haven't said anything about trim, I assume you have it, and that setting can affect the hole shot as well as the plane.