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Posts: 54
| i run a 2006 tuffy 1700 with a 90 etec, looking to purchase a stainless prop any suggestions guys? | |
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Posts: 32954
Location: Rhinelander, Wisconsin | What prop do you have on it now, and how does she run? | |
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Posts: 54
| I have a junkie aluminum 13.25 x 17 and I'm running about 36 top end with just me and my gear with a little lean to the passenger side. I know you said. | |
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Posts: 32954
Location: Rhinelander, Wisconsin | I would think you are taching in the upper range with that prop. If so, you can go to a 19 stainless. I'm running a Merc 90 Opti, spinning a 19 pitch, and it's perfect. Not sure on the Rude prop, though. | |
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Posts: 433
Location: Cedarburg, Wisconsin | The OPTI has a 2.33:1 ratio vs. your 2.0:1 ratio on the E-TEC. So the same prop might not work as well. The OPTI spins 15% more engine rpms for the same propshaft rpms.
Going to SS gives you less rpms than aluminum in most cases. The SS will not flex or slip as much due to the cupping so it's stiffer pitchwise even with the same numbers. Your motor calls for a sweet spot of 5000-5200 rpms within the 4500-5500 rpm range and you should prop it to run there for the best performance from your motor. If you don't have a tach, I believe, at your dealers' shop, you can get a computerized readout from your motor's EMM showing how many hours run and at what rpms. If you check the top rpms on that report you would be able to see the range you run at. Then you would know if less rpms are acceptable. You don't want to be below that WOT sweet spot as that's just making the motor work harder than it has to for no reason. You lose performance and the motor will not run as clean/efficiently.
What are you looking to gain from a SS prop?
Edited by Almost-B-Good 9/6/2011 7:00 AM
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Posts: 54
| Looking for less slip and top end I wanna go faster if I can. | |
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Posts: 32954
Location: Rhinelander, Wisconsin | What is your tach reading now? | |
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Posts: 433
Location: Cedarburg, Wisconsin | Yes, absolutely need to know what rpms you are running at WOT trimmed up! Without that info you are lost.
There are electronic gages available that give you the ability to tap into a wealth of info coming realtime from your motor. If you don't have one, it would be a good investment. I run two 4" gages with my E-TEC that you can set to show dozens of options, like rpms, speed, water pressure, temp, fuel consumption, throttle settings, trim, and many more.
If you are serious about inproving the performance that would be a good starting point.
Then you can try different props and motor heights to establish the very best performance. It takes time and effort. Everything interacts and only trying all the options will give you the results you are looking for. Once you get the rpm info we can suggest props to try. | |
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Posts: 3508
Location: Elk River, Minnesota | Hi Everyone,
Looking at the combination and assuming the 1700 has not changed from 2006 to now much, the boat itself weighs 1100 pounds, with a motor of 79.1 cubic inches for displacement with a 2:1 gear ratio.
My bet is your prop is pretty darn close to where it needs to be but as Steve stated, it might be a little high. The motor itself has an operating range of 4500 to 5500, and to get the best overall performance, you would be better served to make sure the motor is running at (or close to) 5500 when it is just you and your gear. That way, when you get that partner to fish with and his/her gear, you will still be in the operating range of the motor without having to make a prop change.
If you decide to go steel, you might find that a straight switch to steel but staying with the same pitch and diameter might serve you well. Other options that would be out there would be to consider are more aggressive props in a 16 pitch....something similar to a michigan Rapture in 17 pitch, possibly an omc raker (this I think would be a stretch since it is a larger diamter and 18 pitch...might be too much loss in RPM), even a michigan ballistic might do well, but as stated, multiple props must be tried in order to find the best prop for your rig. Many times, a more aggressive prop is desired, which will lower your rpms a bit, but you can gain some of that back with a motor height change. In most cases, motors are mounted too low, which increases drag, but allows for good handling...and is what most dealers will do when they set up a boat.
The RPM numbers are really the most important. If you can get those, it really will lay out where your boat is at now, and what could potentially be done with it. I would say by the time everything is done, you should be seeing a few more MPH, but I would not expect anything more than 40 mph at best.
Steve | |
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Posts: 50
| im at work so im not signed in but my motor is running right at the sweet spot now 5000 to 5200 right were it says it should be | |
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Posts: 433
Location: Cedarburg, Wisconsin | If you have the right rpms now, my next thought would be to try close to the same pitch in a SS that you are running now, like maybe a 16 or 17 pitch Viper or Raker in BRP models. You said your current prop is beat up so maybe the SS would spin easier than you Al prop. That might negate the stiffer blade geometry. I don't know if Merc has a prop that fits your motor in the Tempest Plus line, but they are fine props. You just use the hub kit to adapt to your motor. Again I'm thinking a 16 or 17 pitch.
If you can get a SS prop on and are close to the optimum RPMs you might just be able to raise the motor another hole to make use of the SS cupping, and to get the RPMs back up again. Generally, E-TECs like to run higher on the transom and SS will let you do it. Optimum is having the cavitation plate totally visible above the water while running trimmed up and at cruising speed or higher. Aluminum is not a good choice for doing this as it has less grip than the SS props so it cavitates on turns at higher transom settngs and has less bow lift.
Ideal situation is to find a prop you can try without buying it. Then if it doesn't work you have nothing lost and are closer to finding the best setup. It gets expensive in a hurry if you are trying and buying as it usually takes more than a few trys to find the best prop and motor height. This isn't a quick process getting the very best setup.
Just remember, keep the RPMs up at the 5200 level with your NORMAL load, higher with a light load (5500), and your motor will give you the very best performance it can.
Final though is this. If you get close with a prop you like but aren't quite there, a prop guru can customize it for you to get the rest of the way to the perfect RPMs and lift for a couple hundred bucks. I've been told many times Merc props have the best steel so if you are thinking about this, I'd go with the Merc brand over the newer BRP stuff. Old OMC props had better steel from when they were made in Milwaukee but it might be a bear to find one.
Good luck and keep us posted on your results. | |
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Posts: 3508
Location: Elk River, Minnesota | Hiya,
For ksmusky: The recommendation of a Tempest prop is out of the question since it has a larger hub and a significantly larger diameter than what the suzuki can take unless it has the 25" shaft length and the larger gear housing and a gear ration above 2:1. On that tuffy, I would bet it will be a 20 inch transom, thus you will have the smaller gear housing and will need a prop that is less than 14" in Diameter.
The Viper prop is designed specifically for speed, but I feel you would lose performance since trying to turn something over 17" in pitch would extremely hard to do with a 13-7/8" diameter. It will slip more than an OMC raker since it does not have the cupping of a raker, so it would need to be trimmed down significantly in order to get a decent turn without ventilating. To turn a viper, I would bet you would need to go down to a 15 pitch, which would be great for hole shot, but top end would suffer...
It's a matter of working with props as stated...find a few to try, and one will definitely stand out from the others.
Looks like we have two different people with questions but the same boat?
Steve
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prop suggestions for my tuffy..