A couple of Magnum 27 sports

[Conquistador_del_mar]

I ran across these and thought I would pass them along since there is an interest in them here. Bill

http://miami.craigslist.org/brw/boa/1445925539.html

http://miami.craigslist.org/mdc/boa/1432101360.html

[scippy]

Hey Bill, The green one looks like a sport, but the ad says a 28, doesn't look like a Maltese though.

[Conquistador_del_mar]

Hey Bill, The green one looks like a sport, but the ad says a 28, doesn't look like a Maltese though.

It sure looks like a 27 sport - probably just an error by the seller. I think the 27 sport is actually 27' 5"? Bill

[smidgen too]

It sure looks like a 27 sport - probably just an error by the seller. I think the 27 sport is actually 27' 5"? Bill
They are both sports. The white one was a Volvo boat, it now has Alpha drives. :( It was on ebay many times before.

[OFFSHORE GINGER]

They are both sports. The white one was a Volvo boat, it now has Alpha drives. :( It was on ebay many times before.It now has Alpha drives and what a joke that is . I have to say that for whatever the reason is i would have stuck it out with the with the original drive , hopefully a TRS or did an upgrade to a bravo but Alpha drives J U N K .

[Forrest]

I can just about guarantee you that Alpha drives won't last very long on a 27 Sport.

When I made the move to get rid of the Volvo 280t's on my Sport, I decided to go with something with a little meat on the bones.

[Ghost]

I can just about guarantee you that Alpha drives won't last very long on a 27 Sport.

When I made the move to get rid of the Volvo 280t's on my Sport, I decided to go with something with a little meat on the bones.

Those look great. I loved my old duoprop drive in my 22 Cobalt.

May ask ask what your power and performance numbers are like in the Magnum now? (Also, did you sell off the old drives--just curious, not in the market...yet anyhow. :) )

Also, I am curious what you think about trim tabs with your setup? Critically needed? Nice to have? Rarely used? No need--could do without? Other?

Regards,

Mike

[dammmagnum]

They are both sports. The white one was a Volvo boat, it now has Alpha drives. :( It was on ebay many times before.

Hello Smidgen

I understand that it was a MI boat at one time then headed to the West Coast.
Not sure who put the Alpha drives on it?

Thank you
Best regards
Jim

[Forrest]

Those look great. I loved my old duoprop drive in my 22 Cobalt.
May ask ask what your power and performance numbers are like in the Magnum now? (Also, did you sell off the old drives--just curious, not in the market...yet anyhow. :) )
Also, I am curious what you think about trim tabs with your setup? Critically needed? Nice to have? Rarely used? No need--could do without? Other?
Regards,
Mike
I'm really happy with the DPX Duo-Prop setup. The boat handles like its on rails and prop slip is at an absolute minimum - whic kind of threw a wrench into some of my early-on calculations. The big down side is that you cannot find very much information such the effective pitch of the E-series props, best gear ratios, etc. I'm running E2 props (what ever pitch that suppose to be) and a 1.59:1 gear ratio and I'm still a little short on RPM. DPX drives are available in four- or five-ratios and three props sets (E2, E3, and E4) and that's it. So how do figure all of this stuff out? Buy some DPX drives with a ratio that you think might work, and make sure that you buy them at a great price and start trying props. Jeeze, the neighbor doesn't have any E-series props to borrow? Try scouring eBay for months to find pair matched sets that were never worked in any way for a reasonable price. Anything under $500 a set is a bargain since Volvo-Penta wants about $1200 a set. Before I had it all put together, I had accumulated four set of props; a pair of E3's and a pair of E4's. BTW, I bought the E4's from a heck of a nice guy in the UK.

Anyway, the first time out I decided to run the E3 props. It felt great! Man, it pulled hard and the Magnum handled better than I ever imagined. Then for the full throttle test. Crap! This thing was so over propped that the 383 strokers motors that I built would barely break 4200 RPM!. No need to even try the E4 props sets since they are even more pitch than the E3 sets.
At this point, all the props go straight to eBay in order to attempt recover my prop budget and then the search was on for a set of E2 props. Luckily the all the props sold on eBay and I didn't loose too much of my prop budget. BTW, the E4 sets sold to guy in Luxembourg.

Anyway, long story short the E2 props got me in the 4700 RPM and last and into low to mid 70's. Since Volvo-Penta does not make an E1 props set and a gear-set change will require a second mortgage on my house, I will need to send my second set of E2 props to someone who knows what they are doing in order to get me at least 5000 RPM. Otherwise, I ain't complaining.

As the the tabs, I used them a little bit in the rough Gulf of Mexico but now that I mostly run the Magnum in Lake Eufaula, which BTW, can get pretty rough, but I very seldom use them.

Both of the old 280t were put on a pallets and motor-freight shipped to a board member who bough them a few years back.

[Ghost]

Wow, thanks for the info. (I'd wondered about the whole "how do you know" problem with the drive ratio and props--wow, what a pain. Sounds like the beast is doing really well though. Congrats. What a great boat.)

Regards,

Mike

[scippy]

I'm a little off topic from the previous posts, but seeing how Magnum owner's
with setup experience are here now, I'd like your take.
I'm restoring a 73' magnum sport, I've set aside a nominal amount of $$
for this and decided on installing a twin power setup, I will be replacing
the transom to get a fresh start from the old TRS cutouts.
I've seen a 28' pantera w/6.2L sb's w/ brvo 1's that ran pretty good and
economical. Don't know if the Pantera is simular in weight to the Sport.
377 Scorpian's would be nice, but not sure how much more they would jack
up my budget of the 6.2L bravo package I now set aside for...... Thanks

[Conquistador_del_mar]

I'm really happy with the DPX Duo-Prop setup.

This thing was so over propped that the 383 strokers motors that I built would barely break 4200 RPM!.
Anyway, long story short the E2 props got me in the 4700 RPM and last and into low to mid 70's. Since Volvo-Penta does not make an E1 props set and a gear-set change will require a second mortgage on my house, I will need to send my second set of E2 props to someone who knows what they are doing in order to get me at least 5000 RPM. Otherwise, I ain't complaining.

Forrest,
What a great setup you have there. What HP do you figure your 383s are making? 70-75MPH takes some good power in these heavy boats. Have you taken it out in rough water yet? I'll bet it rides like a dream - :wink:.
I remember reading about guys mixing up their props on Bravo IIIs with some good results for final tweaking of the top speed and RPM range. I have no idea how you would figure out the best combination of the Volvo props, but someone out there probably knows through experimentation if it is worth trying. Just thought I would pass that idea along. Bill

[Forrest]

That's right, the Magnum is a farily heavy boat with no hi-tech, last-MPH hull features such steps, pad, notched transom, or any thing else or els for that matter.
Number one is to make sure that your hull is straight, at least for the last six to eight feet. Some of the old Magnums develop a lump or hump or bump or dip in the bottom. If your Magnum has anything problems like that, you have to fix those issues first. If you don't, your performance and handling will suffer. No ifs ands or buts about it.
Secondly, no matter what props I tried, this Magnum could never fully hook up with the water with the Volvo 280T drives. It was always in the 25%- 30% slip range. I tried Ultras, Federals, and Hill Thrashers. No, I didn't try the Solas since it wasn't ready before I changed to the DPX drives. The DPX drives have the prop slip in the single digits now.
Scippy, if you have the funds available, I think you are doing the right thing by ditching the heavy, power-sucking twin TRS setup. You can't go wrong with a Bravo/ small-block stroker setup. I would even consider a Volvo SX, or if you can find a pair at the right price, a DPX drive setup would be over-the-top. I guess that you can tell that I'm a Volvo guy. I literally stole my DPS drives from where the Harbormaster works, before he got there, for $3K each. That included everything from belhousing to prop nut, including the trim pumps, integrated hydraulic steering and hoses and cooler. The only thing extra that I needed to buy was a Char-Linn steering helm unit and the correct PS pump. Did I mention that all this stuff was a pull from a zero-hour Formula the was going to be re-rigged with #6 drives?
Also, I don't know what the actual HP is on my 383s but they are not anemic. They are similar in build to the 383 I have for sale here on Donzi.net (http://www.donzi.net/forums/showthread.php?t=59146) except that these 383s have Iron Eagle heads (200cc intakes), different pistons (dish), and Stainless Marine Exhausts. I think I'm really in the 71- to 73-MPH range
Yes. I have run her in the Gulf with the DPX set up a few times off of St. Marks, FL, where there are plenty of swells and good bit of chop and all I can say is that the ol' girl performed wonderfully. The DPX drives made all the difference. It was truly a new boat after the installation these drives.
I'm in the ball park with the E2 props now. From what I understand, I don't think there is any mixing of DPX E-series props. I probably need to talk Throttle-Up about making them just right. Even though I have four-sets of E2 props, it still makes me nervous to have someone rework :smash: the blades since so little information seems to be out there on these props.
More pictures in this thread: http://www.donzi.net/forums/showthread.php?t=41340

[Fast Shafts]

Forrest,
I'm also repowering a 27 Magnum Sport. Top speed is not my primary goal. (I've raced for several years-spent alot of money doing it) My goal is all-around performance, getting on plane with 4 people aboard, and cruising at 50mph. What is your opinion of a single Bravo III or DPX in the 27'?? I'm thinking a 500-550 horse engine would push it to the low 60's, do you think this is reasonable?? Thanks in advance!!
Bob

[Forrest]

Forrest,
I'm also repowering a 27 Magnum Sport. Top speed is not my primary goal. (I've raced for several years-spent alot of money doing it) My goal is all-around performance, getting on plane with 4 people aboard, and cruising at 50mph. What is your opinion of a single Bravo III or DPX in the 27'?? I'm thinking a 500-550 horse engine would push it to the low 60's, do you think this is reasonable?? Thanks in advance!!
Bob

Bob, a single big block in a Magnum 27 Sport is a very reasonable power choice and has been done many times before with great success. Given the choice, I would apt for the DPX over all DuoProp drives, due to what I consider it to be a better built and stronger drive than a Bravo III, but on the other hand, the Bravo III is more readily available than the DPX. Also remember, the DPX has an integrated external hydraulic-steering system which works very well and will save you from having to buy a separate aftermarket external system. Also, the DPX is strong. Innovation Marine was contracted to build the engines for Volvo-Penta's fully warranted 600DPX package (pictured below). Innovation built some of the best performance marine engines available anywhere.

http://www.donzi.net/forums/attachment.php?attachmentid=15891&d=1131397767

Another DuoProp drive to consdider is the Volvo-Penta DPS. It's readily available and fits in a standard Mercruiser transom cutout. Basically it's a DuoProp SX drive with about the same HP rating as a Bravo.

Whatever your DuoProp big-block single choice is for your Magnum, 60+ MPH shouldn not be a problem.

PS. I was thinking that this thread should be moved to the "Talk About Other Boats" section.

[mphatc]

So there's several of us here playing with the Magnum 27 in various configurations; single, twin, and eggbeaters . .. and I am in the midst of repowering my 68 Mag 27 and still undecided on the final power set up.
As this thread is taking place under Other Boats For Sale and in a Donzi forum . . and I like the players here !!! and Donzi .net !! so please don't read this wrong . . !! :smash:
Can we possibly all move these discussions to OSO and the Magnum forum? There are more folks there with various inputs and experiences and certainly some would gain from Forrest's experience's as well!
I for one could post a host of questions to Forrest as I'm considering twin 383's, . . .

Respectfully suggested . . .
Thanks,
Mario L.

1969 Donzi Corsican C18 C32
1968 Magnum 27

[Forrest]

Not a bad idea, Mario. I'll be out of pocket until the 23rd, so don't think I'm ignoring you guys.

[Ghost]

... if you can find a pair at the right price, a DPX drive setup would be over-the-top. I guess that you can tell that I'm a Volvo guy. I literally stole my DPS drives from where the Harbormaster works, before he got there, for $3K each. That included everything from belhousing to prop nut, including the trim pumps, integrated hydraulic steering and hoses and cooler. The only thing extra that I needed to buy was a Char-Linn steering helm unit and the correct PS pump.

BTW, I would just crack open my retirement money and buy a pair of these (just what you did) at this price. Today. Even not knowing if I could use my current motors. Even knowing it would ruin the original aspect of my Nova. It would be so good with that setup, I'd bite the bullet in this economy and just do it.

So, if anyone has some, here's a deal waiting to happen.