Estimated HP output - Build Sheet attached
04-12-2018, 06:44 AM
#21
Platinum Member
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I guess I'll have some playing around to do. I was just thinking an estimate on power would help.
The previous owner used both 1.35 and 1.5 gearing in the Bravo drives with the old power. 1.35 for fuel economy, then switched to 1.5 for better acceleration. It was spinning the 24p to 4600 with the 1.35 gearing and old power. It was spinning 25p Mirage+ to 5000 with the 1.35 gears as well.
All things being equal, I figured by the switch to the 1.5 gearing, a 26P 4 Blade would be in order. Add in the new power, that led me to the 28p as a starting point.
I haven't picked up the boat yet, I was just thinking of starting somewhere with the props since it hasn't really been tested WOT since the rebuild.
The previous owner used both 1.35 and 1.5 gearing in the Bravo drives with the old power. 1.35 for fuel economy, then switched to 1.5 for better acceleration. It was spinning the 24p to 4600 with the 1.35 gearing and old power. It was spinning 25p Mirage+ to 5000 with the 1.35 gears as well.
All things being equal, I figured by the switch to the 1.5 gearing, a 26P 4 Blade would be in order. Add in the new power, that led me to the 28p as a starting point.
I haven't picked up the boat yet, I was just thinking of starting somewhere with the props since it hasn't really been tested WOT since the rebuild.
04-12-2018, 08:32 AM
#22
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Thread Starter
I want to stick with the 1.5 - which are in there now. My only point is that all previous prop testing was with old power and old gearing. I was looking for estimated power ratings, knowing I was going to run the 1.5 gear set.
04-28-2018, 10:33 PM
#23
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Thread Starter
Bumping this.
Ran the boat at sea trial. Spinning a 24P Bravo 1 to ~5250 @ 73mph GPS. I dont think these are making the right power. That's with full tanks (200G) and two people.
Wouldnt you think they should be capable of spinning 24p well past 5200 (not that you'd want to)?
500+ hp should spin 26p to that rpm. Any opinions?
Ran the boat at sea trial. Spinning a 24P Bravo 1 to ~5250 @ 73mph GPS. I dont think these are making the right power. That's with full tanks (200G) and two people.
Wouldnt you think they should be capable of spinning 24p well past 5200 (not that you'd want to)?
500+ hp should spin 26p to that rpm. Any opinions?
04-28-2018, 11:51 PM
#24
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Ran the boat at sea trial. Spinning a 24P Bravo 1 to ~5250 @ 73mph GPS. I dont think these are making the right power. That's with full tanks (200G) and two people.
650 RPM for another ~100+HP sounds about right to me.
spinning 24p well past 5200 (not that you'd want to)?
Why not?
500+ hp should spin 26p to that rpm. Any opinions?
Not necessarily. You added HP probably maintained TQ, but carried further.
spinning 24p well past 5200 (not that you'd want to)?
Why not?
500+ hp should spin 26p to that rpm. Any opinions?
Not necessarily. You added HP probably maintained TQ, but carried further.
04-29-2018, 06:32 AM
#25
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Thread Starter
According to the previous previous owner and prior to the rebuild, It used to spin the 24p to 4600 with 1.36 gears.
it now spins the same props to 5200 with 1.5 gears.
The gear change is what is likely affecting the WOT rpm
it now spins the same props to 5200 with 1.5 gears.
The gear change is what is likely affecting the WOT rpm
04-29-2018, 12:45 PM
#27
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Its Clustergear's old boat, and is now the one in the classifieds. He owned it for many years and sold it to the gentleman who I am buying it from. He has been a wealth of knowledge and I've searched his old posts as well. Clustergear ran the 1.5s because he like the acceleration over the 1.36 gears. He never changed the props though and sold the boat with the 1.5 gears in it. The current owner never touched the drives, only rebuilt the motors with the attached build sheets. You would think the gear change alone would require a +2 change in prop, regardless of any new power.
04-29-2018, 12:53 PM
#28
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You put a lot of nice parts in those engines, but unless you make drastic additions like a blower to it, an extra 100hp often doesn’t dramatically change the character of the performance of the boat. Some boats are just limited too. Throw a 100hp on a 29’ Baja and you may see a couple mph but if you throw the same package on a Fountain Fever you may see 8mph out of it.
But more importantly, if you’re hitting 5200 then check for a rev limiter and fuel supply.
But more importantly, if you’re hitting 5200 then check for a rev limiter and fuel supply.
Last edited by Baja Rooster; 04-29-2018 at 12:56 PM.
04-29-2018, 06:12 PM
#29
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04-30-2018, 08:18 AM
#30
Geronimo36
Gold Member
500 HP in a 33 Powerplay will run 76-78 mph with labbed 28's @ 5100 rpm. That's what they runs with 500EFI's.
I just built two 522's that made 670HP and I'm gonna see how high I can spin the 28's. Looking for 88-90 mph. Fingers crossed!
I just built two 522's that made 670HP and I'm gonna see how high I can spin the 28's. Looking for 88-90 mph. Fingers crossed!
