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what prop to run on a 210??? the hallett I just got has a hydromotive 24p four blade....I haven't tried it yet , btu, I think that is way wrong...
my son runs a 24p bravo 1 with a carbed 454....my boat has the hp 500, I'm guessing I have 150 more hp..?? guessing....I would say that that boat would be able to spin a 26p to start...??? whatcha think?
Prop Slip Calculator
Is it important to know your prop’s slip? Only if you care about insignificant, little items like thrust.
Slip is the most misunderstood of all propeller terms, probably because it sounds like something undesirable. Slip is not a measure of propeller efficiency. Rather, slip is the difference between actual and theoretical travel resulting from a necessary propeller blade angle of attack. If the blade had no angle of attack, there would be no slip; but, of course, there would be no positive and negative pressure created on the blades and, therefore, there would be no thrust. The Mercury Racing Prop Slip Calculator (below) lets you quickly determine propeller slip.
http://www.mercuryracing.com/wp-cont...r-propslip.jpg Calculator
- Propeller Pitch
Calculate- Gear Ratio
Calculate- Engine RPM
Calculate- Actual Speed (MPH)
Calculate- Propeller Slip
- Propeller Pitch 24
Calculate- Gear Ratio 1.50
Calculate- Engine RPM 5000
Calculate- Actual Speed (MPH) 64
Calculate- Propeller Slip 15%..
so when I got this boat, the guy said it will run 90 mph.... I walked around back and looked at the prop...24p hydro, with out say'n a word I knew that that was BS...as you can see, at 5000 rpm, with 15% SLIP...64 MPH...GPS...SO KNOWING SOME OF THE FACTS, 24P PROP...1.50 gear, I took a guess, 15%...(might be less) and figuring 5000 rpm, ... nets you 64 mph,... far cry from 90 mph ...lol... unless he took the twin turbos off or something... not gonna happen...
so, my first guess is the prop is too small and it should be able to spin aat least a 26 p...
- Propeller Pitch 26
Calculate- Gear Ratio 1.50
Calculate- Engine RPM 5000
Calculate- Actual Speed (MPH) 82
Calculate- Propeller Slip 0%
so as you can see...to get to 82 mph with this boat.. it would be at 0% slip
at 15% slip, you would be at 70 mph...10% slip would net 74 mph...
so in theory... and facts.. water test is needed... but were bench racing here so lets see what would happen if it could spin a 28p
- Propeller Pitch 28
Calculate- Gear Ratio 1.50
Calculate- Engine RPM 5000
Calculate- Actual Speed (MPH) 75
Calculate- Propeller Slip 15%..
so now we are at 75 mph , that's with 15% slip, you could get to 80mph, with 10 % slip, for that to happen the wetted surface would have to be at a foot...in othe words, the boat would be fly'n on the tabs,... so not to realistic
So, the way I do this is to take some props and a vacume gauge out on the water...first to see how much it struggles to get on plne, then to see if it gets any vacume at cruising speed, and last to see what rpms it will turn...you will actually go faster with a smaller prop that gets to with wot recommended rpm (rev limit)
in this video, I was running a 26p on a 240 open bow,525 power, I would guess this boat would be comparable to a 210 with a 500 hp...so that's why I think the 210 should be able to easily pull a 26p
https://youtu.be/VAv8-_eF6FU
Good lord I miss this hallett, I think it had 40 hrs when I found it, 525 power, big ass open bow people hauler..:jumping-smiley-019::thumbsUp:
https://youtu.be/EkM7jgo4-90
:detective:here's Sues 26' deck boat with a 525...26p prop... I was able to run my secret wepon 29p on this boat, hauled ass...:shock::action-smiley-069:
https://youtu.be/4DH97YFpzmA
sues first day out with her new boat..
https://youtu.be/lnU57C4kQJQ
I actually love halletts, and the 500 hp motors..but I'm not the brand loyal guy that won't say about the problems the 500 hp has...they have their problems , but easy fix's IMO.. #1 is the stock carb... they have to stagger jet it to fatten it up, but they still run lean on 5&7...and that where they like to burn through the head gasket.. somewhere in the manifold design there is a problem...next, the valve train, anything past 200 hrs' you are running on a prayer.... now, that all is gonna depend on how the boat was run for sure...running it WOT ...better check it out..I've had 6 of these motors start to come apart at 200 hrs..the roller rockers and lifters should be replaced... in fact... thats one of the requirement from merc...the next is the blind holes on the head bolts...the bolts bottom out and give false torque readings...with 5&7 running lean, they like to cook the valves, they tulip and will suck the valve/break the stem, and bye bye motor...
https://youtu.be/HAU5F5qu7Vs
after having half a dozen of these motors go south, I made this video....those of you that know what you are looking at can also see where the head gasket let go,... this was one of the more mild ones as I have seen them to where it looked like someone took a cutting torch and burned through the block.. in every occasion , the problem was always between #5 & #7
https://youtu.be/obJdWRmZ9e4
I want that 240 you had. I've heard the 210s like Rev 4s as well.
Sent from my iPhone using Tapatalk
Quote:
Originally Posted by hallett21
I think what they really like, and respond to is no de-fuser ring...the rev four is also a big eared prop and slower..so my gain was best with a solas prop with out the ring
anyone wanna guess or know what prop % slip number will be???
2FF, there is absolutely NO reason with a tall open plenum intake (like the one in your engine pic - post #13) you should have a lean condition on 5/7. I'm not saying it isn't true but I sure can't see ANY logical reason at all. Maybe if it happens on always on the 525 style EFI intake it would make more sense but not on a tall VICTOR type open plenum intake. Run it fatter maybe OR take some timing out of the ignition with a RPM window switch on your MSD OR use one of the many MSD ignition components to bump the timing back at WOT...Quote:
Originally Posted by 2FORCEFULL
Distance from the PRIMARY on the carb?
I have heard of this issue before on BBC but never thought to much about it since I'm a ford guy...
It would be interesting to talk to https://www.facebook.com/gordon.jennings.568 on this topic. He should have some solid input... My view is to jet and run it fatter OR take timing out at WOT (if the problem is only under HEAVY LOAT/WOT)...
merc actually found the problem, that's why they stagger jet the carb to rich'n those cyl...Quote:
Originally Posted by 2manymustangs