cobra marty

Your engine will raise up 3 inches so be sure you have room above it so as to not hit the hatch.

Wild Card 09

The 24 has about as much headroom above the standard motor installation as a 25. There is acres of it. With my raised motor, I still have enough space for a Whipple on a good sized chiller .

If you get the 24 to run like my 25 does - and I`m sure you will - you will love it...........

KAAMA

iTrader: (1)

Wild Card, nice photos. I like the attitude of your hull and how it sits on top of the water.

FYI for anyone reading---it takes A LOT of testing and $$$ for all these combos. Here's what I have experienced. I have a twin engine boat (32' A/T). My boat originally had TRS drives and I immediately removed the TRS's when I bought my boat and installed XR drives with Stellings extention boxes and I used 32" 4-bladed Bravo One props. However, when I removed the TRS drives---which by the way requires a tranny, I left the engines in the same spot. I did NOT moved them back and just used a longer driveshaft between the flywheel and the bearing carrier flange. I liked how my boat would ride across the water---nice and flat attitude, but it seemed a little too bow heavy even with trim. The bow seemed to stick to the water and just didn't sit up on top of the water the way it should for a boat like mine.

So, I had the hull checked and found out I had a pretty good hook going on that I had removed, and then we moved the engines back to a stock bravo installation to try and get the boat to ballance a bit better in hopes that the bow would sit up a bit more.

Once we did that it DID lift the bow a bit as we hoped, BUT now the boat would not ride in rougher water as well and wanted to chine walk above 80mph and I could not control the chine walk without running the K-Planes in the water a bit which had a negative effect on the speed. So, I HATED the how the boat handled and about the best I would see is about 87-88mph.

The stock length Bravo ones (no nose cones) prop shafts I had sat about 3.5"-4" below the hull. I also thought adding some nose cones would be a PLUS. An option I felt would work well was to add some IMCO -2" shorties with their noce cones already casted into the gear case---so, we installed them. The boat was VERY difficult to get on plane with a 4-bladed Bravo one prop, but once on plane I noticed how well the attitude of the boat was and how it would ride across the top of the water and the chine walk had gone away , but I lost about 10mph in the midrange and no gain in top end speed.

So, I installed a pair of new 30" P5X 5-bladed props from Hydromotive----the boat popped up on plane no problem and I picked up most of my midrange speed again and gained a minimum of 4mph at WOT, but now I really like how the boat rides across the water---on TOP of the water with a different angle of attack and new attitude...just a very BIG improvement on handling! I think the P5X props from Hydromotive helped lift the transom of the boat on top of the water as well. I wasn't really expecting it all (-2" shorties, 5-bladed props) to be as good as it all turned out.

I am very happy with the results,....but for the extension boxes, -2 IMCO shorties, P5X props I spent AT LEAST $9000+ per drive/side!

A friend of mine has a 32' A/T like mine. He has 556cid engines with 8-71 superchargers---all rebuilt, new hydraulic roller cams, ported Dart PRO-1 heads, and added some Stelling large extended primary exhaust manifolds with 5" dry pipes and supposedly made 815hp on the dyno---engines were fresh this year. We ran against each other about 5 times last weekend in South Haven---with air temps and humidity that day we ran dead even at 91mph that day. Even in the mid range he could not pull away from me as we headed up to the top of the RPM range. We both were turning 5400rpms that day. I believe one of the ways he could not pull away from me with my 565cid naturally aspirated engines is because of all the equimpment I have hanging off my transom---which he doesn't have, but with same identical boat, I still expected him to beat me badly with his supercharged engines---all in fun.

LAXBAJA

MY 24 OL LOves the 5 blade.
I have 25 labbed high five and my boat handles like a dream, cornering, hole shots, mid range pull, and alot of transom lift.
It always felt like i was on a pocket of air.
When i would jump the boat it would land in the water and it felt like it would spring back up.

Wild card is right, my 24 OL has the deapest engine compartment. I needed to do some measuring with the hatch closed one time and i got in the engine compartment , closed it and still was able to crawl from side of the engine to the other.

KAAMA, it sound like you have a real nice set up now. But as you well know men in general are never satisfied with anything to long. WOMEN, HORSEPOWER, SPEED, It's a tragity but HOLY SH*^><""*%# is it fun.

My quest for bigger and better things will never end. My 24 OL is only the start of my long list of (HELL ON WATER) that i will have in the future.

thanks again for all the great info guys
will talk soon

Wild Card 09

@KAAMA - good post, and interesting results. I admire anyone who has tried so many alternatives on a twin rig. Its really interesting to see what different settups do, and you´ve highlighted an important issue that is good to remember, that it is not just the top speed figure that makes a great boat! If the price is too high to get the last couple of miles, then they are not worth it.

Good recreational boating is generally a mixture of many different experiences, and finding your top speed is only one of them.
However......
In that fabulous movie "The worlds fastest Indian" where Anthony Hopkins plays an old retiree living in New Zealand in the sixties who only lives for his hotrodded and modded 1929 Indian. He still has an eye for the ladies but most of all, he wants to take to the Bonneville salt flats to find out "what she will really do".

As he works in his workshop, the neighbour´s son is often there, asking him the sort of questions only a ten year old could ask.
At one point, wanting to justify his seamingly pointless infatuation with speed, he says to the youngster something like" if I spend five minutes of my life at my top speed, I will have lived more than others have done in a whole lifetime"

........and that made me smile alot!

KAAMA

iTrader: (1)

I must admit, I was almost going to remove the -2" shorties and re-install the stock length lowers and just add some nose cones to them because I didn't think $8000 for the shorties and another $2200 for the 5-bladed props was worth the minimum of a 4mph gain---especially with a loss of about 3-4mph in the midrange because that is where I cruise at 99.9% of the time.

I will tell you the truth, the ONLY reason why I kept the -2" shorties and 5-bladed props was because of the BIG IMPROVEMENT in handling I experienced after the installation! At that point it I felt it was worth the $10,200. The way the boat handles now is awesome.

I suppose if I were to add some 32" 5-bladed P5X's vs the 30" P5X's I now have, then perhaps I would regain all of my midrange cruising speed back as I once had with my stock length lowers and the 4-bladed 32" props I used with them.

By the way, the 30" P5X's I now have on my boat are STOCK/UNTOUCHED props...they're NOT labbed!!!

LAXBAJA

Wild card do all XR drives come with a different prop shaft size.
I was just thinking about that cause all my props are for a bravo 1
Now, If they do fit with the setup im going for, do you think I will be running the same pitch as i was stock????
If not what do you think I'll have to upgrade to.
now i'm running a 23 labbed and a 25 labbed high five. The 25 has cup taken out and the 23 has cup put into it. I would say that i'm running a 24p with the 23 mirage at 5100 RPM, and the high five i spin about 4850 RPM.
I would like to be about 5200 - 5300 RPM when finished.

Also i was running a 1.36 drive and am also running the same gears in the new XR. I've been told the gears in an XR are 1.35 VS 1.36 in the Bravo 1.
Is this true???????

Wild Card 09

Part of the beefed up internals of an XR is the 1 1/4" propshaft.

Do your props haft solid or welded in hubs?

If not, it will be no problem getting the XR hub from Mec racing. However they are expensive ($140). you only really need one, as the prop should slide on it easily.

I haven´t had any need for a 1:36 drive, as I was told that they really become relevant on boats running 90+. So I couldn´t even tell you the exact ratio.

It may not be to your advantage, but shouldn´t hold you back either, as the 23 - 26" pitch range is quite efficient.
But there must be a prop specialist here who will be able to say more about that.

activatorf1

I run a 24 degree , 24 ftl non step old school rocker bottom with an Imco 3 inch box and 2 inch shortie . The propshaft is still 1.25 inch below bottom , I run a new Hydo quad 4X -28 , non labbed , by the way out performed all around compared to labbed bravo one , pitch for pitch .Boat will never blow out , I'm going to redrill transom and go up 2 more inches . Any thoughts ?

LAXBAJA

I finnally finished the the boat, Im going to post some pics this week, before it goes back into storage for the winter.

i went way over board and pulled all the stock rubber hose of and put all stainless braided lines with AN fittings on everything.

diamond plate aluminum (thanks wildcard) on the floor, new carpet, all aeromotive fuel system, hardin marine billet water pump, full twin ram hydrallic steering, two chrome coolers that cool the engine oil, drive oil, power steering, and the fuel.

It has been alot of work but it turned out very nice.

not to mention the $22,000 it cost to do it all (parts only)

Now the question is, HOW DID IT PERFORM??????????????

Well i'm not sure yet, 100 new fittings and alot of leaks to tend to.
Flirting with fuel pressures.
Differant props.

and now its going to get down in the low 40's this week, kind of put a damper on working the bugs out.


But it is faster, how much is yet to be determined.
I'll post some pics soon.