Hydromotive P5s
 

I purchased 2, P5 5 blade 28 pitch 15 ½ diameter props from Hydromotive and gained 6 MPH on the top end so far and I know there is more if I get more seat time. My boat is a 28 Eliminator Daytona Cat, Twin HP 500’s Top Speed So far 100 at 5050 RPM. Past top speed with Bravo 4 blade 30 pitch 15 ½ diameter props 94 MPH. Drive gear ratio 1:32 Here is my Problem. The boat has a problem getting on plane. The props blow out and the engines rev and the boat cant get on plane with 3 people on board. My 2 passengers had to go up in the cabin to get on plane & with 2 people in the boat I can get it on plane with some real gentle throttle work. I would have thought that 5 blades would get better grip so to speak than 4 blades? Any Suggestions would be greatly appreciated !

Diffuser Rings may help out some. But Semi Cleaver props are more difficult to get on at times. It is a trade off sometimes.

Julie

tell us more about your set up? ext boxes? shortie lowers?

No Boxes & Standard Bravo 1 drives no shortie lowers.

If you don't have diffuser rings install them and it will improve. Keep in mind that all though 5B props they are cleavers. That being said they will prove more difficult to plane....trade off.

Julie

Imco Cavitation plates would probably help you immensly. You are the first person I've heard of that has made a clever work on a 28 daytona....Mine and most people that I know who own them need bow lift not stern lift. P5X's work well, but Bravo's are almost always the fastest... those are all with boxes, some with std drives, some with short drives.

Put some Imco plates on and most if not all of your planing issues should disappear. :drink: Also, if you let your motors rev higher...like 5700, your boat will go faster...of course you'll probably have to go down in pitch... How do you have 1.32 ratio, just curious?

I have a 2007 28 Daytona w/twin 496 HO's, STD Bravo drives, 1:36 ratio, no standoff boxes. It came with stock 4 blade Bravo 32 props - which I had to finess onto plane, but was able to do 100 mph in perfect conditions...mid 90's otherwise.

With full tanks of gas, or more than 2 people on the boat, it took some serious patience to get on plane - and if there were any sizable waves when i was trying to get on plane - forget it.

This spring I threw on a pair of 5 blade labbed maximus 30's - and haven't put my 4 blades back on since. I top out at 96 mph now (hit 98mph once, but 96 mph many many times).

With the 5 blade maximus, I am on plane with full tanks of gas and 5 people in the boat without much effort at all...ie. within 5-7 secs would be my guess.

I am bumping the rev limiters at 5150 and am toying with trying stock 5 blade 30's or labbed 5 blade 32

JD I dont know how I have 1:32 gears in the drives. That is what It had when I bought it. Also the rev limiter is at 5350 on the HP500's so why would I want to risk hurting the engines by turning them 5700 RPM? Thanks

Bye the way I didn’t mention that I do not have any center tab on this boat. I called Eliminator about this problem & they told me that I should install a Dana center tab and this will cure my problem. I want to try having Hydromotive install the larger flair ring / defuser ring on the prop 1st to see if it can hook up at low speeds. The crazy thing to me is how locked up the boat is after it is on plane. When I hit the throttle at 40 MPH it pins you to the seat and the boat just keeps going faster & faster. My GPS Speedo is a livorsi & only goes to 100 MPH but I have already gone past the 100 mark. I am going to have to get a 120 MPH Speedo to see the new top speed. The boat feels like it will hit the rev limiters if I have the balls to keep going. These new speeds take some time to get use to. I am cautious at 100 MPH and above. As for the reason the boat likes these props I have no Idea but why do you guys keep calling them cleavers? They are not cleaver props. The blades look similar to the bravo 4 blades just 1 more blade.

NJDAVE:

You must be running the "P5X" then if they look like bravo's (round ears) as many call them...and it does NOT surprise me that those work for you. They lift the bow nicely with std length drives...with short drives they lift the transom too much IMO....but again that is on boats with boxes. "P5" is a clever prop....

Max rpm is a matter of opinion..... We routinely run 500 HP's and EFI's to 57000-5900 with never any problems. Cats like prop speed and rpm, daytona's included.

I'd try the Imco cavitation plates before spending big $ on a center tab. I know someone that had a 28 with 36" bravo's and short drives with no center tab who could get on plane with the cavitaion plates.

JD I am looking at the reciept & these props are not the P5X
they are P5's. Maybe you should try the P5 you might get more speed than you are with the 5X ? Do you have a center tab? If so how do you use it? All the way down to come on plane & then all the way up at speed? They are very expensive & I dont think I would want to install it myself.

Dave....Maybe I should try the P5, but everyone I know who has tried them on a 28 has not been happy with the results. You stated your props look just like a bravo....which P5X's do....P5's are clever props, so that is why everyone is calling them that.....clear as mudd....:drink: take a picture and post it and we'll know exactly what you have. :D

Now that I think about it I do remember someone having luck with the P5's, I think his boat was a 99 also....one difference was his motors center to center (propshaft to propshaft) were like 2 or 3" further apart than mine or most others I had been around. (Mine are 62 1/2" apart) Apparently Eliminator was experimenting with the placement in 99....I think he even turned his props "out" vs "in", but can't remember for sure.

I do not have center tab, and have no issues getting up with P5X OR bravo's...unless I run 36" bravo's which cause some planing issues with lots of people and fuel. I do have boxes though. I do not run cavitation plates, but probably will in the future. Before I had boxes, I had slight problems getting on plane with full fuel and 4-6 people with 30 bravo's. That was 5 yrs ago though.

Here is P5, (left)...see how straight the edge is......and P5X (right)...see the "round ear".....

JD I will take a pic Monday. I am sending them back to Hydromotive to have the larger de fuser ring put on them. They seem to think this will help. I will measure the distance between the prop shafts this week end & post the number. FYI I turn my props in & last year tried them out & the boat was the same on top speed but I did not like the way it cornered in a turn so I keep them turning inward.

fyi...I do have a center tab on mine. I use it to get on plane - once on plane I put it all the way up and don't touch it again until I have to get back on plane.

Yeah, everyone I know with 28's turns them in for the same reasons...but there was that one mentioned that I'm pretty sure turned them out..

How does your boat run with whichever props you have. Do you notice much additional bow lift? or does it still run pretty flat like most 28's do...? I never messed around with props before I installed boxes.

IF you all can successfully run P5 props then this opens the doors for different manufacturers props, ie: Hering and Throttle Up CNC Props. If you are game and I have the correct pitch available for you, I can send you a set to try and then we will all know! Let me know.

Julie

Here is a link to Mercury gear ratios.

http://home.columbus.rr.com/mtboats/...earratios.html

I ran my props turning out for one season and really liked it around the dock. They did create more stern lift and a hop between 70 & 75.

I don't like extra stern lift because it requires more trim for my 28 to ride right. I like to keep the drives as level as possible in rought water such as a poker run.

My friend has a 99 28' with drives a couple of inches farther apart than mine and jdnca1's and he can run stern lifting props such as the P5s.

Jdnca1 is right about keeping the rpms above 5500. The 28 really likes the engines wound up.

I am surprised he can run the P5 as well. I have an 01 28 and I tried out a set of 30P P5's. The boat jumped up but no matter the trim the bow just felt stuck to the water. Top speed was similar to my 30p Bravos. I am back on the bravos now but i would like to try so P5X's or even the maximus one day, if i don't sell it soon. My 01 didn't like the P5..must be in the setup...

Sorry I didn’t get back with you guys but nothing to report. I sent back my props to Hydromotive & I have confirmed they are P5 Not P5X so I guess I have a unique set up. I did not measure the distance between the drive ( just forgot) but I will measure this week end. When I get the props back with the bigger Diffuser rings I will report my results. I hope to get on plane with more low end grip and keep the same mid range & Top end results. If not I will have to decide whether to install a center tab (Ouch on the cost) or try the P5x next. That is probably what I would try. I will let you all know.

Thanks All for the input!!

IMCO cavitation plates....Dont' ignore this to help your planing...I had a hard time believing it myself until I saw it work on other Eliminators...:drink:

Well I have not got my P5s back yet but they are on the way Via UPS. I took out the boat this week end with the Bravo 30P 4 blades and my boat felt like it was 2000lbs over weight! Wow what a difference than with the P5's . If any of you guys say the boat does not like P5's then I must have a unique setup because my boat feels so much lighter and faster with the P5's then with the bravo props. As soon as I get the new & improved P5's back with the new defuser rings I will report my results. If I can get on plane I will be hands down keeping them ! I can say that the Bravo props suck on my boat. Here is an example. P5's 3000 rpms 55 MPH & 3500 RPM 66 MPH compared to bravo 3000 RPM 45 MPH & 3500 RPM 57 MPH. My boat feels like the Bravo props are sucking my hull deep into the water & the P5’s are freeing up the boat to be light and pack a lot of air just like the hull was designed to do!! Light & loose is fast!. By the way my drives are exactly 5 feet apart exactly 60 inches.. I measured them this week end.

5 blades are lifting the rear of the boat, thus making it lighter feeling. also the 5 blades will have less slip thus the higher speeds for the same RPM.
Im currently going through the same prop dilemia's and Id love to try a set of P5's but I have a bow rider and fear the bow may not lift as well.

QWKRN I am learning that these boats don’t need bow lift. The hull will float the bow on its own & the bow lifting props are actually sucking the ass down into the water rather than freeing the boat up to air out. You should definitely try a P5 & not a P5X!. I had spoke extensively to the guys at Hydromotive & they also said the P5X is not the prop you want for a cat hull. So don’t listen to all the people telling you to use a bow lifting prop they don’t know what they are talking about. I am telling you from 1st hand experience the P5 is what works best with these hulls. The only problem is getting on plane & I just received my props back today with the longer diffuser rings so I will report my results after this week end. If this helps me get on plane with less prop blow out than I am really happy! If this does not help than I will have to install a center tab to help flop the nose over when planning.

I have a center tab on my boat. I feel that unless you have the wide dana tab its a waste of money. I have the regular K plane style tab on mine. I dont disagree about normal closed bow cats responding well to the P5. Im just finding that the bow rider is a different animal. I may be trying a set of 28p Maximus props that are smaller diameter and have been labbed to see how those work. Right now my slip is at 18% Id like to get it down.

A cat with a big bowrider is different then one without one. I have hell getting my bow up. My boat is way faster when the back seat is full of big boys then just me by myself. I am using a P5X with good results. I have faster top speed with a lab bravo but since I have such a high X the boat would not stay on plain below 30 mph. I have not tried a P5. Might call Throttle up and have them send me one to try.

QWKRN are you saying that your tab does not work for you? I was thinking of a 12" x 24" Tab if the new larger prop defuser
does not work.

Does it work? Yes slightly.... Would I spend more than $500 to add one of this size? Not a chance. Ill be down at the lake this weekend. Ill measure the tab I have and let ya know the size. It does help but not much. Now if it were the big wide tab im sure it would make a huge difference.

Well when I put the P5's on the boat jumped up unlike what you are saying...My boat does it completly different. Once on up it felt like the bow was stuck in the water and would never float right. I think it has more to do with the setup. I haven't tried a p5x yet but the p5 was just wrong on my boat....

There are just so many factors to take into account with these boats....boxes/no boxes, X diminsion, POWER, top speed (100 is differnt than 130) drive spacing, fuel load, etc, etc. My boat's " X" is 1" below the bottom of the boat, with short drives (1" above) and P5X, it has way too much tail lift...from feel and video evidence. With std length drives, the P5X carry the boat very well. However, a bravo prop is still faster.... Slip for mine runs ~12.5% with Bravo's and just under 8% with P5X. Maybe some transom lifters with std length drives are worth a try though..

my boat has boxes and 1.36 ratio standard length bravo drives. My X is I believe even with the bottom of the boat. Im going to check that a lil closer this weekend.

Well Guys I am going to see how well I can get the P5's to hook up with the longer diffuser rings on them this week end. If the boat can get on plane like it does with the Bravo 4 blades then I am done! The way my boat feels with the Bravo props SUCKS! It feels about 2000lbs too heavy & the prop slip is a joke compared to the P5's. If the new rings don’t work then I will be installing a center tab for sure. If you guys look on eliminator's web site all of the new boats have them & when I talked to them directly the guy I spoke to said all of the new boats have them to get on plane because of the high X all the new boats are being built for top speed. Dana wants 2,500 for the center tab OUCH! then to have it installed? probably cost a total of 3000.00

Save your money. :drink:

I tried the P5 and could not get on plane, the P5x's work great. I also tried unlabbed uncut Maximus and the holeshot and midrange were incredible but top end was awful I could not get to high rpm even with a 28 Maximus. I have run 30 Bravos labbed and unlabbed and of everything I have tried the 29 P5x is by far the best on my boat I am getting about 8% slip at WOT with light fuel and cold air. I do not have a tunnel tab and the P5x's do not blow out getting on plane for more than a second you can push the sticks all the way and leave them there unlike the bravo's.

How did the reworked P5's end up running?

I have the Same problem. The props blow out & I think we found the problem. My drive shower water pick ups are fractions of an inch away from the prop blade and we think this is causing the turbulence & there for causing blow out. I am going to temporarily remove the drive shower pick ups and re try. If this solves the problem I will re locate the water pick ups. I will let you know after I test.

I know this thread is a little old, but I wanted to chime in. I hade P5's on my 99 Daytona when I got it. I have the same power as you. They are a semi cleaver prop. I a small issue with prop blow out, but not bad. I did not like mine because of the slugish top end on the boat. It ran 96-97mph on LOTO with the 5blade 30's and ran 102mph with the 4 blades. I know our x-dimensions are very low from the factory that year.

My boat did pick up 1 mph by turning the props in vs. out. I have attached a video of a 97mph run with the P5's.

http://media.putfile.com/at-speed