First rigger to build for impba p (4s) or Q(6s)

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I don't know if IMPBA has the same stupid max size rules that NAMBA has, but the current 34 inch boats are too small. The R4 is only 30 inches and is built around a 5000mah battery that is too small for a serious P-lmtd let alone full P. Competitive boats are pulling north of 200 amps and running in the mid 70s. If you go Zip, get the bigger boat. If you plan to race, ask here before you buy a power system.
 
I don't know if IMPBA has the same stupid max size rules that NAMBA has, but the current 34 inch boats are too small. The R4 is only 30 inches and is built around a 5000mah battery that is too small for a serious P-lmtd let alone full P. Competitive boats are pulling north of 200 amps and running in the mid 70s. If you go Zip, get the bigger boat. If you plan to race, ask here before you buy a power system.
I'll come looking for you
 
I don't know if IMPBA has the same stupid max size rules that NAMBA has, but the current 34 inch boats are too small. The R4 is only 30 inches and is built around a 5000mah battery that is too small for a serious P-lmtd let alone full P. Competitive boats are pulling north of 200 amps and running in the mid 70s. If you go Zip, get the bigger boat. If you plan to race, ask here before you buy a power system.
my 33fe takes about 4000+w to get into the 70's. Around 300A.

plain simple fact is with castle ESC's easily pumping out 300A+ the boats are just over-powered and something really has to change with FE. Either current limiting or something.
there are ESC's on the market with current limiters built in such as spektrum (160A) and hobbywing (180A).
 
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The easiest current limiter is a restriction on maximum prop diameter. That said, length limits are stupid. As technology advances, you get fast, undrivable, little boats. This is not as bad for riggers yet, but is happening in the other P classes.

The old motor list system worked well for the P limited classes. Darren Jordan did a huge series of motor tests that could have been used to generate a new list with a level playing field. If we stick with the current ( pun intended) motor rules We will be running a standard motor in any case. Today it's the TenShock motor.

Lohring Miller

1732634269253.jpeg
 
The easiest current limiter is a restriction on maximum prop diameter. That said, length limits are stupid. As technology advances, you get fast, undrivable, little boats. This is not as bad for riggers yet, but is happening in the other P classes.

The old motor list system worked well for the P limited classes. Darren Jordan did a huge series of motor tests that could have been used to generate a new list with a level playing field. If we stick with the current ( pun intended) motor rules We will be running a standard motor in any case. Today it's the TenShock motor.

Lohring Miller

View attachment 332242
 
Absolutely technology advances things get faster Things become unstable I agree 100% with that but a motor doesn't win the race it's the driver that counts you can be the slowest boat or the fastest boat who wins the rabbit or the turtle.. correct me if I'm wrong but that's just my experience as a yachtsman( ocean racing,americas cup sailor) the last 26 years and Apba stock outboard hydro and runabout
 
The easiest current limiter is a restriction on maximum prop diameter. That said, length limits are stupid. As technology advances, you get fast, undrivable, little boats. This is not as bad for riggers yet, but is happening in the other P classes.

The old motor list system worked well for the P limited classes. Darren Jordan did a huge series of motor tests that could have been used to generate a new list with a level playing field. If we stick with the current ( pun intended) motor rules We will be running a standard motor in any case. Today it's the TenShock motor.

Lohring Miller

View attachment 332242
if they spec a hobbywing 180A it wont matter what prop or what KV or what battery, The boat will slow down automatically.
 
If you do that, the ESC becomes the fuse. In the old P limited class the motor was the $80 fuse. Limiting the current with prop diameter means nothing is the fuse if you get equipment that is sized correctly.

Lohring Miller
 
How so? Hobbywing ESC's do not catch of fire if you trip their current limiter that Im aware of. and if you are hitting the limiter you should probably bring it in a put on a smaller prop.

are we really teching props to check their pitch? Cause you can just keep adding pitch and get around diameter restraints. and none of that means anything if you also do not regulate KV. So then motors need to also be teched.

versus just mandating a simple $120 ESC.
 
Dave you are kind of right. At a certain pitch/diameter ratio things get wonky and the boats won't work. Simply limiting diameter will limit watts put to the water without limiting equipment choices or burning things up. Pylon racing has a class where they had out APC 9x6 props. Everyone uses the same prop. It has been succesful for many years. Limiting the prop diameter and removing hull size limitations would yield larger boats capable fo running at the current speeds and finishing heats. More fun and better racing. This is very easy to enforce. a kv limit would also help, but is alot more work to enforce. Another method that has been proven to work would be to require watt/minute limiter as in F5D for limited classes. Now we have completely hijacked this prro guys thread.
 
Dave you are kind of right. At a certain pitch/diameter ratio things get wonky and the boats won't work. Simply limiting diameter will limit watts put to the water without limiting equipment choices or burning things up. Pylon racing has a class where they had out APC 9x6 props. Everyone uses the same prop. It has been succesful for many years. Limiting the prop diameter and removing hull size limitations would yield larger boats capable fo running at the current speeds and finishing heats. More fun and better racing. This is very easy to enforce. a kv limit would also help, but is alot more work to enforce. Another method that has been proven to work would be to require watt/minute limiter as in F5D for limited classes. Now we have completely hijacked this prro guys thread.
You are all good I'm new to the race boat world for RC but other than that I'm a Speed Demon I have an RC car called Limitless I've got it to go 127 mph I'm so close to hitting 150
 
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