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I have an Eliminator 27 Fun Deck with a 525. Running the 1.5 XR drive with a 26p Bravo 4 Blade. I can spin this prop to 5000 rpm in the current 100 plus Texas heat and run 74 mph on GPS.

I am happy with the speed but holeshot and low speed planning is not as good as I like (for watersports with the kids).

I have found some used props - 24p Maximus 5 blade (15 5/8 diameter) and a 25p P5X. (15 diameter) Which would be best and why?

From what I understand. a 4 blade Bravo is actually about an 1" less than sold - so my 26p is really comparable to a 25p. I also understand that when going from 4 blade to a 5 blade requires a drop in pitch. So If I have a 26p Bravo that is really 25p - then I need a 24p 5 blade. So I am concerned that the 25p P5X maybe too much but also concerned that the 24p Maximus may not be truly 24p.

Thoughts?

Thanks
Stacy

bbladesprops

I think you will prefer the 15 5/8" diameter Maximus. The long diffuser ring will help to plane quickly and the larger diameter will keep you on plane at the slower speeds required for some water sports.

Brett

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Thanks Brett. I have read where others have reduced the diffuser ring on the Maximus as well as reducing diameter. Should I be concerned with the larger diameter of the maximus since my boat has a higher than normal X-dim?

bbladesprops

A high "X" dimention is a reason to use a larger diameter. Try the full 15 5/8". We can always cut the diameter down. Keep the long diffuser ring as well since it can be removed as is needed post base line numbers and reactions.

Call me if you want to discuss this in further detail.

Brett

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Brett

I will give you a call tomorrrow. I was hoping that the larger diameter might help with the higher x dimension but was not 100% confident. I bought this prop used so I will give it a try and then see what if anything needs to be done and what it will cost!

Thanks

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The boat came with a 26p Bravo 1 4 blade prop. With the stock 26p prop, I thought that planing was a chore with a lot of bow rise. Pulling my kids on the tube at slow speeds was challenging as well.

Tonight I tested with a 24p Maximus 5 blade. All testing with both props was done in 100 plus temperature with 3/4 tank of gas on the left and 1/4 on the right. Speeds are from an Autometer GPS speedo.

26p Bravo I 4 Blade (all stock 15 1/4 diameter)
NOTE: Getting on plane with more than 3000 rpm and the prop will blow out - 2500 would allow it to plane at about 1/2 throttle. This prop needed much less trim than the Maximus. At 2800 - 3000 rpm seems like the prop is slipping or cavitating as the boat feels loose and RPMs will fluctuate.

Time to plane: ??? (will get on Sunday)

RPM____MPH____Slip______Comments
2500______22______46%______WaterSports
3000______36______27%
3250______40______25%
3600______51______14%
4250______62______11%
5000______74______10%______Gets to 5000 quick

24p Maximus 5 blade (all stock 15 5/8 diameter and full diffuser ring)
NOTE: needed more trim with this prop to break the hull loose and obtain speeds. On plane 2200 rpm is all she's got - wide open.

Time to plane: 9 to 10 seconds

RPM____MPH____Slip______Comments
2200______22______34%______Watersports
2500______30______21%
3000______41______10%
3500______49______8%
3750______53______7%
4000______57______6%
4500______63______8%
4800______68______7%______4800 max RPM - Slow to get there

Calculated slip numbers are lower with the Maximus - some look almost too low.

With the 26p Bravo, getting on plane is a chore. 2500 to 3000 1/2 throttle, bow rises high, s-turn and she rolls over. With the Maximus, bow doesn't rise as much but full throttle and 2200 rpm is all its got. I need to get the time to plane with the 26p Bravo.

With the Bravo, I needed minimal trim 3 to 4 on the indicator to obtain speeds. The Maximus required much more 6 to 7 or more to obtain the speeds. Bravo pulled quicker to 5000 RPM than the Maximus did to 4800 rpms.

The Maximus seems more stable at all speeds and eliminates the rpm fluctuation between 2800 and 3000 that I get with the bravo which is due I am sure to the Bravo just not hooking up and slipping at this speed.

Not sure how the larger diameter of the Maximus factors in - it is definitely a bigger prop as I was initially worried about it hitting my water pick up for the drive shower. The Maximus has the solid PVS plugs - I am tempted to yank them to see how it responds with none. I just noticed on Mercury's website Maximus® | Propellers | Mercury Racing that it says that the 15" diameter is for "the awesome performance Cats and go fast party boats" so I guess the diameter could be part of my problem. The website also says "The shortened exhaust tube (some people refer to it as the diffuser ring or barrel) settles the stern of select hulls, resulting in a 2-4 mph increase in top-end speed. " This is consistent with what I have been told about removing 5/8" off of the diffuser ring.

I am going to run the Maximus tomorrow and then put the 26p Bravo back on Sunday to get back to back testing. More to come.

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Brett

I saw you returned my call today and left a message. By the time I got the message, it was already past quitting time in your area.

See my testing results above. I will test more this weekend but would like your take on what I need to do to the Maximus to get it to rev more when planning and help on top. Is the diameter simply too large and is the diffuser ring scrubbing off speed? What does it cost to do these things?

Thanks

bbladesprops

The best idea is to talk on the phone.
I am behind on my call backs so bear with me if you have left a message.

Thank you,
Brett

Itsallgood995

I have one that may work for you. 14.625" w/ shorter tube.

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WHat boat was this on? Diameter seems way smaller than the Bravo at 15.25"