indian summer

[MDonziM]

Never got a picture off from the LG visit a month or so ago but the other day was sweet. Still, 71 mph is all i can get out of her... 94' hull 96' 502 mpi stock w/ Gil/Mercury Performance exaust. Labbed 25"mir+ . 5050rpm.

[Pismo]

You are hitting the limiter with that prop which is probably down to about 23-24" pitch after the labbing. Get a labbed 27" Mplus or a labbed 26" Bravo 1 prop and you'll get a few more mph. That motor should be able to turn a stock 25" MPlus to 5050-5100rpm. Or raise the rev limiter to 5250 or so. The motor can handle it easily.

[MDonziM]

Pismo,
Thanks. I didn't realize how the rev limiter works. I thought it was a cut out at some rpm.(like 5600) Your'e saying that the limiter wont let the rpm's exceed 5100 ?

[Pismo]

If your engine is a stock Merc 502 Magnum then the limiter is set at 5050-5100rpm(depending on which manual you read) and that's it.

[BigGrizzly]

We did Tomahawk with a un labbed Turbo. Hia 454mag did 74

[MDonziM]

I dont know if tamahwk is a boat or an owner but from all ive read re props for 22's it seems to me that the mirage plus is the fastest. A lot of variables to the top speed results: fresh water/ salt water, tide, not to mention varriables/ diferences between identically equipped boats( drive installation height, engine wear etc.)Pismo gets 74.5mph with the same boat same prop same rpm. I dont stay @ WOT more than 20 sec. or so. But it does feel like the max torque is in the 4500 rpm range so I'm going to take Pismo's advice and try more pitch.

[Pismo]

I guess the Turbo is a good prop as well. I have not tried it. From what I have read it will turn even more rpm than a MPlus so since I am hitting the limiter with my 25" MPlus, I would have an even worse problem with a 25 Turbo, I would need a 27" (Which I then feel would be a little too much) A labbed to 5000rpm 26" Bravo I may be the perfect set.

[MDonziM]

Pismo,
Did you not like the handling w/ the 27" mirage plus? (since you had the fastest speed w/ it) Or do you feel its important to reach 5k rpm?

[BigGrizzly]

Concisering I have run the 27 MPlus against the 27 Turbo Same day same boat and founf the Turbo to be faster and handled better. Tomahawk is a boat as well as the owner and we both found the same thing.I have tried mor than 15 different typs of props not including different prop pitches on my boat and others. This includes Mercury Lab finished props. Rember honest testing with a GPS is truth, Not with the pito tube speedo. It is true some boats may be faster with the Marage+, but untill you tyried the others your just guessing. On my 22 the TurI was 3 MPH faster and handled better(opinion) than the Marage. If you look at the forums you will find this is what others have found. I don't want to hear the lab finished deal because the prop is no longer a Marage. I will always remember at Eufala someon's lab finished marage looked more like my Turbo lightning than my marage+. If it workes better for you then use it. Unless you have tried the others don't say its the best. I do love the TurboI, it has solved a multitude of boat problems for me in the past. Now my new favorite is the Turbo TXP on my application. at Sarasota I put a Turbo Fusion on AIR22 boat and he liked it better than the hydromotive that some say is the best. I put a TXP on Catch 22 and speed was the same but accelerated harder than his labbed Hydromotive, but liked the Hydro better- for his application(did not have the Fusion to in the right pitch for him, maybe next time. Its about application, if you don't try it you dont know. The M+ ist a good prop, but it may not be the best prop. I have been lucky working at a marine engine manufacture, because I had props up to the ceiling to try. and I still don't know all the answers. It is still try untill you find the right one.

[MDonziM]

BG,
Thanks for the input, i agree w/ you, you don't really know till you try. I don't know your setup so if you had mine which prop would you try next? Are the Turbo, Turbo txp, Hydromotive all 4 blade? I havn't heard of the txp. Know a site to shop / compare?

[blueliner]

All I can say is that everyone is entitled to their opinion but to say that a mirage plus that has been labbed is not a mirage plus anymore can be said about any prop then. I used a stock mirage plus 27p right out of the box and went 77 mph gps speed with two guys in the boat. The only reason I got it labbed was because I was still pulling 5100 rpm's. Now with the labbing I have more surface area like a 28p but with less rpm's. Everyone has an opinion and until u try diff props all of our "foolisophizing" is just that... A bunch of beer league boat enthusiasts... I love the prop that brett modified for me and I think everyone gives the mirage prop a bad name cuz of porposing... The boat porpoises no matter what prop but if u have ur boat trimmed properly the porposing goes away. I don't have any on my boat anymore
It is a pure pleasure to drive!!!
I haven't tried the turbo so I can't comment on how that prop%performs but all I have had are mirage plus's and have had nothing but good reults from them.

Concisering I have run the 27 MPlus against the 27
Turbo Same day same boat and founf the Turbo to be faster and handled better. Tomahawk is a boat as well as the owner and we both found the same thing.I have tried mor than 15 different typs of props not including different prop pitches on my boat and others. This includes Mercury Lab finished props. Rember honest testing with a GPS is truth, Not with the pito tube speedo. It is true some boats may be faster with the Marage+, but untill you tyried the others your just guessing. On my 22 the TurI was 3 MPH faster and handled better(opinion) than the Marage. If you look at the forums you will find this is what others have found. I don't want to hear the lab finished deal because the prop is no longer a Marage. I will always remember at Eufala someon's lab finished marage looked more like my Turbo lightning than my marage+. If it workes better for you then use it. Unless you have tried the others don't say its the best. I do love the TurboI, it has solved a multitude of boat problems for me in the past. Now my new favorite is the Turbo TXP on my application. at Sarasota I put a Turbo Fusion on AIR22 boat and he liked it better than the hydromotive that some say is the best. I put a TXP on Catch 22 and speed was the same but accelerated harder than his labbed Hydromotive, but liked the Hydro better- for his application(did not have the Fusion to in the right pitch for him, maybe next time. Its about application, if you don't try it you dont know. The M+ ist a good prop, but it may not be the best prop. I have been lucky working at a marine engine manufacture, because I had props up to the ceiling to try. and I still don't know all the answers. It is still try untill you find the right one.

[thriller]

Steve,

You mentioned in your post that you don't have any what?/ tabs???
You removed them? :confused:

I will be sending my 31p props to Brett for a tune up this winter. he is happy with my numbers but there is always a couple of mph he can dial out of most props that come his way:boat:

MM

[Last Tango]

I would listen very carefully to Big Grizzly. He is not just another guy on this board. He is a VERY experienced professional in the marine industry, particularly when it comes to props, prop engineering, and selection. He is far more than just another opinion. Those of you new to the board in general will find this out. And Tomahawk is one of the legend boats/owners on this board. They live on Lake Lanier in Georgia and spend more time on the water than you do in bed, which from the sounds of a couple of these responses, is considerable.

[Pismo]

Please post what boat and what engine you guys are running with these prop results. Thanks

[BigGrizzly]

B-Liner Like I said before your boat runs well and I'm sure Bret did a great job. The big 27 M-plus did not get the bad name from porposing but from loosness under throttle. All props will porpoise under cirtain conditions. The only way Brett could put more surface area on the prop is to add metal. Now the prop is not as designed. It is clear to me that Brett did a good job on your application. Also remember your boat is the fastest 496 HO I have encountered and you don't have trim tabs which could account for this. I in no way am I suggesting anyone remove their tabs. I wouldn't, some times you should use them. I said in a previous post why the 27 M-plus got its bad rep., Because sombody said it was called the widow maker and others beleived it and repeated it so people think it is fact without trying it. Most people can't pull a 27 pitch prop! I found the prop to be uneasy and loose but not dangerious. The Turbo worked better and was faster. Because of diameter and pitch progression the M--plus changes from one pitch to another. Example: a 23 Turbo turnes more RPMs than a M+, a 25 Turbo turns about the same as a M+. one more variable. The typical blade varience of the M+ is 1/2 inch so a 27 can be a 27.5 or a 26.5. Also one blade can and is different. Beleve me I have gone to great pains to measure them as well as other props. I won't deal into this any deeper, because it gets real boring and opens the door to "My friend said" stuff! I'm glad you can pull these numbers from your boat. I don't know of another 22 Donzi 496 HO that can pull a 27 prop. period!
The TXP is a 3 blade and a 4 blade, both are available yousee after 26 pitch the Turbo and the M+ Lose effiency and stability. This is one reasion Precision no longer offers it. the TXP and OSI and OSII, and Fusion have taken over. At Sarasota Dwite found the Fusion to be every bit as good and better then the Hydromotive on his application. One of the reasions I am on this board is to save heart akes and money to others. Yes I sell props but I don't want to sell you the wrong prop. Let someone else do that. How many times have you heard "I put on a new prop and my boat goes slower".
My boat that I take to most Rallys is a 22 Criterion with a TRS outdrive a Merc Trans. the engine is a 690 HP Procharged 502 carbureted engine and I turn a 29 or 30 TXP depending the day. It will run 86+ MPH with a full tank of fuel and 4 people on board. This is what we call my wife's motor, because she likes it better than the stock one when she drives it. My motor I hope I will never have to put in this boat. I hope this answers any questions

[blueliner]

So are u saying then, even with a turbo, it wouldn't be big enough, I would be hitting the rev limiter, and would have to get that labbed as well?? Cuz I would try a turbo prop no problem, but if a stock one is not going to work, than I'm back at square one again... I could have just kept the 27p stock. I did picj up nearly 2 mph right out of the box, but I would probably have done the same with the turbo, and again I would have been close to the rev limiter. That is the main reason to get it labbed was to get the rpms down at WOT. I also have got better midrange on the boat, cruising is now close to 58 mph at 3500 rpms, so that I am very happy with as well. Btw, I have k-planes on my boat.

[BigGrizzly]

No, usually if you lab a prop you gain RPMs. what labing does is thin the blades which in effect gives it less friction and sacrifices strength. What it sounds like brett did was add pitch to your prop as well as metal. You stated that he added blade surface, if he did he could in effect have made it a 27.5 or a 28 pitch, which is the only way you would lose RPMs. A TurboI 28 was never available to the public. The TXP or Lightning would be the better option. Since your going faster with your boat than anyone else I wouldn't change anything. However if experimentation and fun is whats instore, I would park that Brett prop and don't change it in any way,then experiment with other props. You see I am not fond of labbed or modified props. There are props for almost every application. If you modify a prop and bend it there is no guarentee that rhey can reproduce it again. close but not exactlly. When I raced we would tweek and/or weight one blade to get an edge. on an old boat I had i found one blade thinner than the rest and it really went well. Replaced it with another same prop and the boat slowed. measured it to fine 3 thick blades. That is how I got into the prop thing.

[blueliner]

you are correct and i wasn't clear. brett, made my prop larger( more pitch) for more thrust and then labbed it to bring the rpm's up again. when i first got it it wasn't labbed enough. i could only get 4900 rpm's and was slower than the stock 27p. he then worked on it some more and now i'm turning 5025-5050 in calm water. i'm waiting for a little bit of chop to see if i can get another 100 rpm out of her and go faster. it has just been so calm lately, not the best for trying to go fast.


No, usually if you lab a prop you gain RPMs. what labing does is thin the blades which in effect gives it less friction and sacrifices strength. What it sounds like brett did was add pitch to your prop as well as metal. You stated that he added blade surface, if he did he could in effect have made it a 27.5 or a 28 pitch, which is the only way you would lose RPMs. A TurboI 28 was never available to the public. The TXP or Lightning would be the better option. Since your going faster with your boat than anyone else I wouldn't change anything. However if experimentation and fun is whats instore, I would park that Brett prop and don't change it in any way,then experiment with other props. You see I am not fond of labbed or modified props. There are props for almost every application. If you modify a prop and bend it there is no guarentee that rhey can reproduce it again. close but not exactlly. When I raced we would tweek and/or weight one blade to get an edge. on an old boat I had i found one blade thinner than the rest and it really went well. Replaced it with another same prop and the boat slowed. measured it to fine 3 thick blades. That is how I got into the prop thing.

[BigGrizzly]

Cool, now we know it is a Brett prop and all the mistry is clear. I hope you get 2 MPH out in the rough. Just remember in order to go 80 you need to do it at least twice, or it is a fluke. Good luck!

[Pismo]

I agree, I hit 77.1 GPS in my 22 once but could never repeat it so 75.5 became the "official" top end because I got it many times. Lots of trim.