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.