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I have a "new to me" Eliminator Fun Deck with a 525 with a Bravo XR drive with 1.5 gear ratio. Previous owner stated that he had it set up with a higher than usual x-dim which I believe because if you trim it too high, the drive shower will contact the underside of the swim platform.
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.
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)
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
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.
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 | Actual Speed | 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 | Actual Speed | 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.
Unsure - it is way better getting on plane than the Maximus - 5.5 seconds although the bow rise is a bit much, it doesn't last long. Planing was the main reason for looking for something other than the 26p Bravo 4 blade and possibly the ability to run at a slower speed down low. 
