Allyfishing
Well-Known Member
on an XB21 2+2?? Or any other XB21 for that matter? How does a Pro ET compare pitch wise to another 4 blade prop??
Inquiring minds want to know??
Craig :beer:
Inquiring minds want to know??
Craig :beer:
Anyone ever tried a Merc Pro ET....
- Thread starter Allyfishing
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bigtis
Active Member
I tried it on an xb2003/225promax combo, and it was too much stern lift, and too much bow lift, but ran overall pretty well. I do believe though that they are known for having fragile blades, "tend to crack."
Allyfishing
Well-Known Member
Yeah, I heard about all the cracking etc. but I am curious how it would run on my boat and what pitch to use. Do ya go up or down in pitch compared to an over/thru prop?
Thanks for the reply there bigtis junior!
Craig
Thanks for the reply there bigtis junior!
Craig
Bobalouie
Active Member
If you are running a 3 blade now, you should probably go down an inch or two in pitch with the 4 blade. The drag created by the extra blade in the water will not allow the engine to rev as high on top end. I am not sure what effect (other than holeshot) that changing from an over/thru would have. Maybe Todd will jump in here and educate us.
TBuck2003
Moderator
Craig,
The Pro ET will turn about the same Revs as yours, so it would be the same pitch to try. He is going from a 4 blade to a 4 blade so it should be real close. Holeshot will have different results from overhub to Over thru. Also the O/T tube will have more tail lift than an over hub. So the boat attitude will change.
TBuck
The Pro ET will turn about the same Revs as yours, so it would be the same pitch to try. He is going from a 4 blade to a 4 blade so it should be real close. Holeshot will have different results from overhub to Over thru. Also the O/T tube will have more tail lift than an over hub. So the boat attitude will change.
TBuck
Allyfishing
Well-Known Member
Thanks Todd, that's what I was trying to find out. Running characteristics of an over hub vs a O/T. How is hole shot affected with the ET? What height difference and trim?
I still have to find the time and place to try the 26 QIV OT again and see if I can drive it to the max. Larry showed me the max height on the JP with the load I was carrying that day plus two people cuz the arse end almost came loose. :shock: Way too much stuff in the boat. First rally so the wife and I had everything in the boat but the kitchen sink. The next day we took the 2 fold up chairs out, the extra cooler, the extra fishing tackle another prop, and some clothes. LOL
I don't think the QIV OT 26P will hit 6750R's. I'm wondering if the PM is actually too light for that 21 foot hull therefore propping may be different. I think too much!
Craig
I still have to find the time and place to try the 26 QIV OT again and see if I can drive it to the max. Larry showed me the max height on the JP with the load I was carrying that day plus two people cuz the arse end almost came loose. :shock: Way too much stuff in the boat. First rally so the wife and I had everything in the boat but the kitchen sink. The next day we took the 2 fold up chairs out, the extra cooler, the extra fishing tackle another prop, and some clothes. LOL
I don't think the QIV OT 26P will hit 6750R's. I'm wondering if the PM is actually too light for that 21 foot hull therefore propping may be different. I think too much!
Craig
whipper
Well-Known Member
You bring up an interesting point about the 21 and the lighter power. From what Ive understood Darris made the 21 to accommodate the 3.0 lt. Just as the older models the 2.5. Power to weight is everything with a boat because of the resistance of water as we all know. What prop is normal to run well on a 21 with a 3.0 may not be the best for your setup. I would also tend to think that basic setup rules would have your motor with more setback to run as designed perhaps also. I'm just guessing like you said I think to much to!:banghead
Hears what I think as an example. Being 100+ LBS lighter at the stern to get on the pad with all that hull weight would require say 14+ inches of setback seeing your loosing the advantage of torque with a PM over a XS and the wieght factor. The props with lots of Stern lift may have to much stern lift so a more neutral lifting prop may be required with the right work done to it to raise the weighted bow just right. Just a thought. I know other boats in that size range granted not an Allison need a fare bit of setback but run way faster when setup this way with 2.5,s over the boats with less setback that are over 2000lbs rigged.
I might be way out in left field but it makes sense to me.
Hears what I think as an example. Being 100+ LBS lighter at the stern to get on the pad with all that hull weight would require say 14+ inches of setback seeing your loosing the advantage of torque with a PM over a XS and the wieght factor. The props with lots of Stern lift may have to much stern lift so a more neutral lifting prop may be required with the right work done to it to raise the weighted bow just right. Just a thought. I know other boats in that size range granted not an Allison need a fare bit of setback but run way faster when setup this way with 2.5,s over the boats with less setback that are over 2000lbs rigged.
I might be way out in left field but it makes sense to me.
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Allyfishing
Well-Known Member
James, thanks for that explanation. I honestly didn't know that Mr. Allison actually designed/intended the 21 footers to run the 3 liters. I was under the impression that the 2.5's were all he wanted on the big boats since the rating plate in the boat states up to 225HP.
TBuck propped me with a 26P QIV-OT to get 6750RPM's WOT and I am not even close to those RPM's. Admittedly, I know I am still a newbie at driving but as soon as I get the bow up to where ya hear the water under the hull and that rattle sound the back end gets a bit free kinda.
At the rally Larry Owens and I went out for a ride with that prop on to see what we could do (there was too much extra weight in the boat at that time) and it took forever to get on plane with the JP all the way down. At a speed run Larry felt the rear end get loose with the propshaft about 3/4" below pad with that load. I'm not sure about the trim angle.
The best handling and speed for me so far is with a TXP 27P 3 blade. HUH?? Not supposed to be on an Allison. But that prop is like a Tempest Plus with alot of rake to carry the bow. So I've asked myself that very same question James if I should have more set back to help the 225PM settle in the back end.
And, I was not thinking that I should be running the same props that the 3 liters guys are running but more like not trying to run the same style props the 2.5 Liter guys are running on the XB02's and XB03's. The prop of choice on those boats have been proven time and time again to be the QIV-OT!!
Again, am I thinking too much??
TBuck propped me with a 26P QIV-OT to get 6750RPM's WOT and I am not even close to those RPM's. Admittedly, I know I am still a newbie at driving but as soon as I get the bow up to where ya hear the water under the hull and that rattle sound the back end gets a bit free kinda.
At the rally Larry Owens and I went out for a ride with that prop on to see what we could do (there was too much extra weight in the boat at that time) and it took forever to get on plane with the JP all the way down. At a speed run Larry felt the rear end get loose with the propshaft about 3/4" below pad with that load. I'm not sure about the trim angle.
The best handling and speed for me so far is with a TXP 27P 3 blade. HUH?? Not supposed to be on an Allison. But that prop is like a Tempest Plus with alot of rake to carry the bow. So I've asked myself that very same question James if I should have more set back to help the 225PM settle in the back end.
And, I was not thinking that I should be running the same props that the 3 liters guys are running but more like not trying to run the same style props the 2.5 Liter guys are running on the XB02's and XB03's. The prop of choice on those boats have been proven time and time again to be the QIV-OT!!
Again, am I thinking too much??
whipper
Well-Known Member
The boats were designed after the production of the 2.5 other than the race motors and theres no warnning for motor wieght like on previous hulls. The 225 when these boats were built is a 3.0LT. Im just going of the top of my head and sure I heard someone say who knows Daris the 21 was for a lot of reasons but to accomidate the 3.0LT was one of them. I think power to wieght with a strong 2.5 and the right setup you should be able to run with a 3.0LT being lighter. The 3.0 LT has lots of tourque but I would think still with wieght savings that sould balance that out.
What is your setback? Did Darris recomend a setback for you? I would ask him what he thinks you should be running for setback and motor hight. Your 2.5 225 is a paticularly good one whith what youve done to it and should prove to be a great runner on any hull. Your way under 400 LBS and the 3.0,s are 505lbs dry. That in its self is big advantage on water I would think. When running more wieght though there is no replacment for displacment to a point.
What is your setback? Did Darris recomend a setback for you? I would ask him what he thinks you should be running for setback and motor hight. Your 2.5 225 is a paticularly good one whith what youve done to it and should prove to be a great runner on any hull. Your way under 400 LBS and the 3.0,s are 505lbs dry. That in its self is big advantage on water I would think. When running more wieght though there is no replacment for displacment to a point.
catfish123
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Doesn't Neal (GotMyAllY) have a very similar set-up? Isn't he running a 225X on a 21 footer?...........As I recollect, he has run some pretty impressive numbers on his.
GotMyAlly
Well-Known Member
I've ran 85. Setup wasn't near perfect. Motor too low on the jackplate and running a box-stock prop at the time. It's got more when i get the motor moved up and the prop labbed.
Of the props I've ran, I like the quad IV X-OT the best so far for fishin. The quad IV-OT still gets the nod for a top end though.
Of the props I've ran, I like the quad IV X-OT the best so far for fishin. The quad IV-OT still gets the nod for a top end though.
Allyfishing
Well-Known Member
HI Neal...thanks for the input. By no means am I complaining or unhappy with my rig. I've been in boating heaven ever since I picked it up in TN last Sept. and drove her home.
Maybe I am carrying to much gear in the front lockers. Reason I'm saying that is I tried a practice run on good water on Cherokee one last time the last day of the Rally and my wife was along and all of a sudden the boat just went to the right. Not bad or anything but shocked the heck out of me and I had no idea why or what the heck had happened. My wife, on the other hand, was freaking out asking why I suddenly changed my mind about where we were going and why did I turn off like that. I just confessed about this today to her, by the way, that what happened was not intentional and the boat just id it. She's not happy!! LOL!!
Anyway, I've thinking about that every day cuz I was not jacked up higher than 1/2" below pad and barely neutral trim. I was running maybe 78MPH at the time.
Neal, what engine height have you been running for 85MPH and how do you trim it? What all do you carry in the different compartments front and rear? I had a good talk with ALLISONMAN at dinner one night and described the sound I have heard once or twice while running after I bumped the trim up. The only way I can explain it is it sounds like a bunch of rattling under and behind me. That's when I have a harder time keeping it running straight. When I don't hear that I can keep it going.
I just keep thinking that I am missing something or don't have things quite right. That's why I appreciate your input cuz you have more the same engine on the back of a 21. Is your Prosport different in weight?
Maybe I'll call the Allisons and go over some of my concerns and setup to see what they think.
Maybe I am carrying to much gear in the front lockers. Reason I'm saying that is I tried a practice run on good water on Cherokee one last time the last day of the Rally and my wife was along and all of a sudden the boat just went to the right. Not bad or anything but shocked the heck out of me and I had no idea why or what the heck had happened. My wife, on the other hand, was freaking out asking why I suddenly changed my mind about where we were going and why did I turn off like that. I just confessed about this today to her, by the way, that what happened was not intentional and the boat just id it. She's not happy!! LOL!!
Anyway, I've thinking about that every day cuz I was not jacked up higher than 1/2" below pad and barely neutral trim. I was running maybe 78MPH at the time.
Neal, what engine height have you been running for 85MPH and how do you trim it? What all do you carry in the different compartments front and rear? I had a good talk with ALLISONMAN at dinner one night and described the sound I have heard once or twice while running after I bumped the trim up. The only way I can explain it is it sounds like a bunch of rattling under and behind me. That's when I have a harder time keeping it running straight. When I don't hear that I can keep it going.
I just keep thinking that I am missing something or don't have things quite right. That's why I appreciate your input cuz you have more the same engine on the back of a 21. Is your Prosport different in weight?
Maybe I'll call the Allisons and go over some of my concerns and setup to see what they think.
GotMyAlly
Well-Known Member
bout 3/4" below the pad. My motor is too low on the jackplate and that is as high as I can go. It still wants more motor height though.
Allyfishing
Well-Known Member
Thanks Neal. Do you carry much in the way of fishing stuff in the front deck lockers? How many rods? I started at 1/2" below on up to 1/2" above the pad. Maybe I should go back to 1/2" below and concentrate on more trim. I think I am under trimmed yet. I need someone to drive beside me and observe my rooster tail and trim angle.
catfish123
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I would check the trim by levelling the bottom of the pad. Once that is perfectly level, then put the trim setting to exactly where you have been running it on the gauge. Then with a torpedo level, check the prop shaft to determine how it compares to level or neutral trim, etc. This to me gives you a much better reading than trying to rely on someone watching it. I just checked mine the other week and although I would have thought I was running a fair amount of positive trim, I was not.....just a VERY small amount above neutral.
Allyfishing
Well-Known Member
Now that sounds like a great idea Bob. I'll check that before I go out again. I marked my trim gauge a while back where neutral trim should be but it may be off. This is a good idea.
Thanks
Craig
Thanks
Craig
GotMyAlly
Well-Known Member
I have probably 10 rods in the boats. A couple of hard bait boxes up front, a spinnerbait box, and probably 15 lbs of soft plastics. My trolling motor is also a heavy monster. (Minn Kota Fortrex). I also just added an amp and a couple speakers under the dash. I haven't ran it since I put that under the console though. I've never had a problem with lacking lift on this boat, but I don't have a clue where I'm running as far as trim goes. I never calibrated the trim guage........i just drive by feel.
Allyfishing
Well-Known Member
Thanks again Neal for the reply. I have 12 rods in the center locker and probably 45 - 50LB's of tackle in the front lockers. My TM is the 82LB thrust (65LB) Motorguide.
Do you notice any difference in the sound under the hull when you are at ideal trim? And what does it sound like?
Thanks for putting up with my stupid questions! LOL
Do you notice any difference in the sound under the hull when you are at ideal trim? And what does it sound like?
Thanks for putting up with my stupid questions! LOL
GotMyAlly
Well-Known Member
I guess you're referring to the water on the hull. I never thought to use the sound as a gauge when I'm trimmed right, but my 03 did the same thing. Once the hull frees up and you are on top of the water instead of in it, the sound does change. Almost like you can hear every little ripple echo thru the hull.
I think the trolling batteries were put in the front deck to balance the boat with a 3L engine. Your engine is much lighter and I would guess your weight balance is too far forward based on this and what youve said in your posts. I am actually nervous for you at this point. You definetly don't want a prop with stern lift. If I were you I would move all of my tackle too the year compartments and see how it feels. Your boat turning right on you like that is scary. Mine did that once and it did it all the way. very scary and took a long time to heal up. I moved my trolling batteries to the rear center compartment. Killed my holeshot but a monkey could drive my boat safely now.