Which SS Prop Manyfacturer Do You Recommend?

[Senderofan]

Please forgive me for this naive question. I'm trying to figure out which stainless prop manufacturer to go with....and if I should make any changes in pitch?

I have a 2001 Lund Fisherman with a Merc. XR6 (2.5 liter) and a 15 hp kicker. Currently the boat has a BlackMax 14.25" by 21 pitch prop on it. Trimmed in she'll do about 5200 rpm with little weight in it. Trimmed out a fair amount I'm getting to around 5400-5450 rpm, again...with just me in the boat. Merc. says WOT is 5000-5600 rpm. I tried to get some info. from Scream and Fly...and the guys there said I need to increase the top rpm to 5800-6000 rpm.

Having said all of this....is there a preffered SS prop manufacturer that y'all go with? Also, should I be trying to spin the motor faster?

Thanks in advance for any information....sorry if this topic has been beaten to death...I did a search but can't come up with any consistency.

Wayne

 

[MikDee]

Re: Which SS Prop Manyfacturer Do You Recommend?

IMO, The Mercury props are some of the best design's, that's what I found anyway over the years, their Mirage props are one of the Best design's, and command a high price probably a lot to do with that. One simple suggestion, If it's safe, and recommended to get to 6k rpm, maybe you can raise your motor on the transom a bit (cavitation plate above the bottom some) like at least an inch, for more speed, & rpm.

 

[jimmbo]

Re: Which SS Prop Manyfacturer Do You Recommend?

I vote Merc too! They have more designs than any other brand.

 

[walleyehed]

Re: Which SS Prop Manyfacturer Do You Recommend?

That Boat responds best with a Turbo 1 vs. any other prop...I've personally tested that. I did not Run any merc prop that ran in the proper rpm range that would do more for the over-all performance than a Turbo1 will.
The boat must be set up for the Turbo 1 though. for best performance, the engine must be raised to a certain "X" demension that there is no set figure or rule for.
The second best prop for that combo would be the Stiletto advantage series which can be maximized by engine set-up, as with any prop.
Yes, Merc has many designs, but most of the SS series cover a std replacement and the rest are targeted at either sterndrive-such as the Mirage-which has little bow-lift, or the higher HP market.
They do have some specialty props for certain apps, but nothing that will out-perform the Turbo or Stiletto that makes them twice the cost...
Your Lund would appear to be larger than 18ft with the numbers given with a 21P...what Length Fisherman is it?

 

[Senderofan]

Re: Which SS Prop Manyfacturer Do You Recommend?

Thanks for the responses...I greatly appreciate it. Who manufactures the "Turbo 1"? My boat is 18' 6" and is a deep, wide boat....at least when comparing to other brands.

Does a 21 pitch sound like it's too much for my boat??

Thanks Again,

Wayne

P.S.,

I know it's early to be thinking of changing props....but I had surgery five weeks ago.....been laying around thinking of what to change on my boat.

 

[walleyehed]

Re: Which SS Prop Manyfacturer Do You Recommend?

21 sounds steep for an XR6 on that boat.
The Turbo and Stiletto are both from Precision Propeller. The Stiletto series is sold right here in the iboats mall at good prices...the Turbo Series is available only from Certain Dealers that sell only after consultation due to being application specific.
We're running very similar boats except I have a tad more HP.
I can spin a 19P Turbo1 over max recommended by about 200rpm. I would guess I'm at a bit higher altitude but I've done some compensating by some engine tweaking to obtain a bit better performance at my elevation.

 

[Senderofan]

Re: Which SS Prop Manyfacturer Do You Recommend?

Thanks much for the information. I'll have to check it out. I live in west central Minnesota. It's a rural area....so there are a few small boat dealers in the area. I don't think they probably have a whole lot of different props to offer...other than factory. According to the general rules of changing pitch...If I were to drop to a 19 pitch....and being trimmed up to where I can run the 21 decently...I should see WOT @ 5800 rpm. That's 200 higher than Merc says is the max. I believe the next motor up from mine,175, is rated for 5800 rpm. I'm wondering if perhaps my carb's can't feed that speed? Evidently the changes from 150-175-200 in the 2.5 V6 is carb's and exhaust tuners...maybe some slight other tweaks.

Does your motor seem to work fine going 200 rpm over max?? I wouldn't be running my motor over the max rpm....just want to make sure it's running efficient and not lugging it.

Wayne

 

[walleyehed]

Re: Which SS Prop Manyfacturer Do You Recommend?

I have ran my 200 up to 1200RPM greater than recommended...I built the powerhead for a purpose and with about 700hrs on it in 2 yrs, it's been flawless except for sucking the 1/2" vent line shut at WOT....we won't talk about fuel economy at that rpm...
I installed Boyesen reeds when I built this powerhead, which does 2 things...it increases fuel efficiency and the ability to idle down to RPM values that are unreal...they also allow airflow to continue above that 6400-6500 rpm mark, which is where stock SS reeds seem to want to start flutter, or "float".
As Dhadley would explain this..."this engine is just an airpump"...it'll run out of fuel/air before you can really get to a point where there would be any serious stress on the rotating mass.
The reason I go this far into the engine issues is because most tachs are off by 100-200. and the engine don't know the difference.
And if you happen to go with a Turbo, the 19P will pull as hard as your current 21. The turbo must be run higher..it'll bite where most won't so you lose that extra gearcase drag and you can get some of the RPM back with the rise. The manner inwhich the prop lifts the boat can cause a rise in rpm as well if less wetted surface is present.
If ya want a good prop, the Stiletto can do some good things, and if you are now running near the top of you max range of RPM, I'd stay with a 21.
If you decide to go with a Turbo, let me know and I will get permission from the board to give you 2 places I know you can buy the Turbo with great support for set-up, and I'd go 19P on the Turbo..it'll run the same as a std 21 with no changes to engine height, but something we will need to do to get the most out of what that prop is designed to do..it's very simple and usually will uncover the hidden performance you didn't even now was there.

 

[Senderofan]

Re: Which SS Prop Manyfacturer Do You Recommend?

Walleyehed,

I can't thank you enough for the information!! I had innitially thought about engine tweaks...but I'm intimidated by my lack of knowledge of two stroke engines. I really think my rig could benefit from the engine winding up more.

If you have a recommendation for a Turbo dealer....and if it doesn't violate forum policies...I'd certainly appreciate the information. I did write a dealer in northern MN that handles them. I'd really appreciate the ability to work with a dealer to find the correct prop for my needs.

Could you explain one more thing for me? From your test data...you compare "Slippage" between the various props. I'm assuming this is an unwanted situation for a prop?? What is an acceptable amount of slippage?

Thnk you very, very much for sharing this information with me. It really helps me make a better decision on a prop.

Take Care,

Wayne

 

[walleyehed]

Re: Which SS Prop Manyfacturer Do You Recommend?

On the style of boat we both have, the Turbo1 will show around 10+/- 1% when set up correctly. a Good number, and possibly the lowest slip found will be on Bassboats with pads at around 8%.
Most of the Deep-V's out there with typical set-ups are in the 14-18% slip ratio range..we can do much better than that. And yes, we want the slip ratio as low as possible..this is a measure of efficiency of the prop.