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Hey everybody, I bought my first boat a few months ago ('89 LIberator 241) after spending last summer on an '88 211. The previous owner repowered my 241 with a 7.4 MPI so i thought this boat might scoot. Well I was wrong. The 211 would do 55 GPS'd anyday with 2 ppl. I can only get my 241 up to 38 GPS'd with two ppl and full tank of gas. The prop is a Merc Marine Offshore Series 48-825902A 46 21P 4 blade aluminum. 1.50 ratio. My max RPM has been 4700. Doing the math I've got about 39% prop slip. The boat does have bottom paint which I thought might add some drag. Any suggestions on how to make this boat faster or is this what I get for having such a big heavy boat and a stock big block?

Thanks for any input.
 

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sounds like more than a prop problem with that low of performance, is your tach correct? engine running on all 8?
I had an 88 211 Libby that had a mildly built 300 HP small block that only ran low to mid 50s GPS, mine ran best with a Ballistic prop but your heavier.... it did have that built in hook from the factory like most of these hulls(more like a built in trim tab)
after you determine if your engine is ok try any stainless 4 blade you can get your hands on, Rev4, Bravo, Mach
I still have the Ballistic if your interested
 

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55 may be optimistic, but should do better than 38. I would look at prop. RPMs in the ballpark by the sound of it. Bravo drive now? 1.5 ratio?
 

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Don't take this the wrong way if you know, however, I have to mention it since we have had a few people come on to the site with performance issues just like yours. After mucho time, it was discovered they did not know about and/or use the outdrive trim and tabs if so equipped.
 

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Discussion Starter · #6 ·
First let me say I've only been a member of this site for a couple days and I love it! Thank you so much for your input.

Now to answer a few q's: Yes its a Bravo One with 1.5 ratio.

And no, I didn't take it the wrong way. I do know how to use trim and trim tabs.

Now about checking to make sure my tach is correct. Since the MPI has a rev limiter can't I rev it in neutral til it hits the limiter and see if that corresponds to the reading on the the tach. I guess I just need to know what the rev limiter is set at. 4700?
 

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THats crazy your only hitting 38 GPS I got a 241 Liberator with a 454mag 420hp carbed hittin 57 GPS all day long at 4800 rpm. I would switch to a stainless steel 3-blade Mirage Plus 23p. These Libbys like the 3 blades. Post some pics of your Libby so we can see.

Oh yeah Welcome to the club, theres alots of Libby lovers in this club.

As far as checking your Tach I would take it to a pro reving ur boat up that high sound like an unnessesary risk. Just my .02 cents
 

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Religion said:
Hey everybody, I bought my first boat a few months ago ('89 LIberator 241) after spending last summer on an '88 211. The previous owner repowered my 241 with a 7.4 MPI so i thought this boat might scoot. Well I was wrong. The 211 would do 55 GPS'd anyday with 2 ppl. I can only get my 241 up to 38 GPS'd with two ppl and full tank of gas. The prop is a Merc Marine Offshore Series 48-825902A 46 21P 4 blade aluminum. 1.50 ratio. My max RPM has been 4700. Doing the math I've got about 39% prop slip. The boat does have bottom paint which I thought might add some drag. Any suggestions on how to make this boat faster or is this what I get for having such a big heavy boat and a stock big block?

Thanks for any input.
You should be doing better than 38mph. But still you have got to remember that our boats are a big hunk solid built fiberglass and are in no way a speed hull. My 211 is very deep and heavy. Your 241 is bigger and heavier. Compared to todays size measurements standards you are running a 29' beak boat That is why libs they last forever if the hulls a kept dry. With my 330 454 I could only get 55 with 25" Mirage Plus 1.50 drive that I bought for my re-powered 454 mag that is going to have around 450hp. If I can run around 65 gps I will be very happy.
 

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65 might be asking for alot 60-62 I would think is more realistic. Like you said big and heavy, but I love the cockpit room, and the cuddy is good size too.
 

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RSCHAP1 said:
55 may be optimistic, but should do better than 38. I would look at prop. RPMs in the ballpark by the sound of it. Bravo drive now? 1.5 ratio?
i agree ............................. put remove the bottom paint , unless you plan on keeping her in the water all the time . I have a friend same boat , 330 H P , 23 P mirage low 50's
 

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I had a 241 with a 540CI 600HP big block and bravo drive. 70mph on its best day.

With the 7.4MPI, which I belive is 310HP, id say you should be around 50mph with botom paint. Ditch that prop, try a 21P mirage plus, or a 19p mirage plus three blade.

Slow boats, but built real well. try a mirage prop and let us know the results and go from there
 

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Discussion Starter · #12 ·
offshore ginger said:
i agree ............................. put remove the bottom paint , unless you plan on keeping her in the water all the time . I have a friend same boat , 330 H P , 23 P mirage low 50's
I would love to remove the bottom paint. How do i do that without damaging the gel coat? I've heard that once it's on there it's on there?
 

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I would think you could wet sand it off, would be alot of work though. Then buff it a couple times after. Or take it to a pro, that might get expensive. I think your problem is your prop, I know a couple guys with bottom paint on their Libbys, and they`re running alot better then 38.

Post some pictures of the painted hull so we can see.
 

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I am going to throw one more out there and I hope I am wrong it could be water logged. If you can get it weighed.

Steve
 

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Looks pretty good Religion, are you going to stay with those Religion decals on the sides? If you want to go back to the 241 Liberator decals let me know I just had Raceline Digital make new decals for mine turned out great. They should still have the measurements from mine to crank out new ones for you.

Check it out
 

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SweetEmotion said:
Looks pretty good Religion, are you going to stay with those Religion decals on the sides? If you want to go back to the 241 Liberator decals let me know I just had Raceline Digital make new decals for mine turned out great. They should still have the measurements from mine to crank out new ones for you.

Check it out
:laugher: :laugher: :laugher: :laugher: :laugher: thank's i was going to ask that same question :a9:
 
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