How much power is P-Spec power?

[NativePaul]

I'm trying to find out how much power a P-spec power system has, specificly the UL-1 system because I hear that it is the best and what folks are running in their JAE21s, but I would be interested in hearing about the SV27 and BlackJack systems too for comparison, has anyone run an eagletree or other datalogger on their P-Spec boat? Or if you have run down to LVC and timed the run I would be interested to hear what runtime you got.
If all you Pspec runners could list your setups and amp draw/ run time i would appreciate it, I am after the following info:-

Boat Class: P-Spec hydro, P-spec offshore, P-spec tunnel, etc.

Motor: UL-1, SV, BJ, or any other your club allows.

ESC: is it the stock ESC for your motor or are you using another, if so what is it, if not do the rules restrict you from doing so or is more just not needed for that motor?

Cells: I assume everyone is on 4s but are you all on 4s1p or is anyone using 2p? What brand, capacity and "C".

Prop: For myself I don't need to know what prop you are using, the info I am after is just, what stops you from propping up further? Motor heat, insufficient motor torque dropping the revs too much, ESC heat, runtime etc. However if you are willing to disclose it, I'm sure there are many potential P-speccers that will read this and could use your make/size/mods info too.

Amps/Time: If you have Eagletree data, a graph would be ideal but peak and base amp draws would be fine, what sort of voltage the cells are dropping to would be helpfull too preferably form somewhere in the middle of the run. or if you have run from fully charged cells to the LVC what was your runtime? with the runtime and the cells you use we can work out the average amp draw


Note.
I am not trying to offend sport boaters here but if you spend long periods of time at partial throttle rather than just backing of for an oval corner then getting back on it for the straight then whilst your Eagletree data would be valid for my purposes your runtime data wont be so please make sure that in the runtime section you note that your time includes extended partial throttle usage.

If for example you have a SV27 and everything runs cool but you don't prop up because whilst faster the boat flips all the time, then that is fine and you made the sensible decision, but what I am trying to ascertain here is the maximum capabilities of the P-spec power systems alone, not that of the hulls they came out of or get fitted in so if that is the case please make sure that in the prop section you put that the Hull is what stops you from propping up further.

SAWrunners/2lap racers, can you make sure that you put in the runtime section that is what you do and that the motor/esc may overheat running a full race distance, and a note in the motor and ESC sections saying that they are uncooled if you don't run watercooling would be good.

Here's a template to make it easier for you to reply, cut/paste it then fill in the blanks.
Boat Class:
Motor:
ESC:
Cells:
Prop:
Amps/Time:

Thanks in advance for your participation, you rock!

[Hydromaniac]

I run a lot of P-Limited or spec classes here are a few set ups.

Boat Class: Vintage Fast scale 1/10, 36 inch Shovell Nose Hydro.
Motor: SV-27
ESC: Hydra 120
Cells:4s 1p Hyperion G-3 5500 MAH
Prop:X-445R
Amps/Time: pull 3000 mah on a 1 mile run approx 2 minutes 30 second



Boat Class: P- Limited Offshore 29 inch mono
Motor:BlackJack 26
ESC:Hydra 120
Cells:4s 1P 5000 Mah, Brand varies
Prop: X645 Detounged, tip rolled
Amps/Time: pulls 3400 Mah in a 4 minute marathon.

Boat Class: P- Limited Sport Hydro
Motor: UL-1
ESC:UL-1
Cells: 4S1P 5000 Mah, Neu Energy
Prop: X542 Detounged
Amps/Time:1400 Mah For 1 mile approx 2 Minutes

Boat Class: P- Limited Crackerbox ( Still in tuning Stage)
Motor: BlackJack 26
ESC: Hydra 120
Cells: 4s 1p 5000 Mah G-3 Hyperion
Prop:X442
Amps/Time: 2800 Mah in 1 mile approx 2 minutes 20 sec

On all of the total Mah draw includes an additional 1/8 mile full mill lap so total MAH draw is for 1 1/8 mile. I have my set ups figured for a full race cycle. Hope that gives you a bit of information.

[NativePaul]

Thanks very much for your times and Mah uses there Hydromaniac, thats a way of doing it that I hadnt though of and works very well.
using your mAh used and times I got the following amp draws, and used 3.5v/cell under load to estimate the power.
P-limited scale hydro SV27, 72A 1008W
P-limited offshore BJ26, 45A 630W
P-limited Sport hydro UL-1, 42A 588W
P-limited crackerbox BJ26, 72A 1008W

I do have a couple of queries, I was expecting the offshore to be low on power as it has a set runtime like we have over here, but I wasnt expecting it to be that low only using 3400mAh out of 5000mAh in the time or 42A when the same motor,esc combo in your crackerbox pulls 72A showing its capable of more, what stops you from propping up more on this setup? I was shocked at the power of the UL-1 combo in the LSH, it uses even less power than your offshore, I note that its the only one not running a hydra ESC, is the UL-1 ESC the weak link that stops you propping up further?

Thanks again Hydromaniac, and I look forward to more data like this from others.

[Hydromaniac]

Thanks very much for your times and Mah uses there Hydromaniac, thats a way of doing it that I hadnt though of and works very well.
using your mAh used and times I got the following amp draws, and used 3.5v/cell under load to estimate the power.
P-limited scale hydro SV27, 72A 1008W
P-limited offshore BJ26, 45A 630W
P-limited Sport hydro UL-1, 42A 588W
P-limited crackerbox BJ26, 72A 1008W

I do have a couple of queries, I was expecting the offshore to be low on power as it has a set runtime like we have over here, but I wasnt expecting it to be that low only using 3400mAh out of 5000mAh in the time or 42A when the same motor,esc combo in your crackerbox pulls 72A showing its capable of more, what stops you from propping up more on this setup? I was shocked at the power of the UL-1 combo in the LSH, it uses even less power than your offshore, I note that its the only one not running a hydra ESC, is the UL-1 ESC the weak link that stops you propping up further?

Thanks again Hydromaniac, and I look forward to more data like this from others.

All of my boats run pretty loose, I look for the best handeling prop as well, some props cause torqe roll and certain hulls that become boucey I opt to prop down a bit and let the motor unwind and use the RPM instead of torque, I win many races with these set ups and my equipment lasts forever. The crackerbox has a subsurface drive and runs a little wetter due to hull design also not tuned yet, It will get better but due to nature of the drive line and hull I expect a bit higher amp draw and Mah usage.

[Jeepers]

Here is a boat that I data logged

Boat: Vacu Pickle
Motor: Sv27
Esc: 120amp
Cells: Neu Energy 5000 30c
Prop 42-55 detounged s&B
Amp Draw" 88amp peak, 60 amps cont. 1100 watts
this is what my Eagle tree showed.

[Brushless55]

Here is a boat that I data logged

Boat: Vacu Pickle
Motor: Sv27
Esc: 120amp
Cells: Neu Energy 5000 30c
Prop 42-55 detounged s&B
Amp Draw" 88amp peak, 60 amps cont. 1100 watts
this is what my Eagle tree showed.

Sean, how different was the reading from your Eagle Tree?

[Jeepers]

not sure what you mean?

[Brushless55]

Dude!
I am so sorry, I was texting and typing at the same time..

[teach]

Boat Class: LSH sport hydro (Dark Horse shovel)
Motor: BJ 26
ESC: BJ 26
Cells: 4s (what ever I haven't blown up yet)
Prop: usually 642 or 445
Amps/Time: 1800ish 1 mile race about 2 minutes.

Motor and speed control stay very cold. I don't prop up because I can't finish most races yet. When I have a clue what I am doing I may prop up.

[Jeepers]

Here is a boat that I data logged

Boat: Vacu Pickle
Motor: Sv27
Esc: 120amp
Cells: Neu Energy 5000 30c
Prop 42-55 detounged s&B
Amp Draw" 88amp peak, 60 amps cont. 1100 watts
this is what my Eagle tree showed.

this boat runs great and is fast and everything comes in cool but the driver cant handle more speed right now (my dad)

[Hydromaniac]

Thanks very much for your times and Mah uses there Hydromaniac, thats a way of doing it that I hadnt though of and works very well.
using your mAh used and times I got the following amp draws, and used 3.5v/cell under load to estimate the power.
P-limited scale hydro SV27, 72A 1008W
P-limited offshore BJ26, 45A 630W
P-limited Sport hydro UL-1, 42A 588W
P-limited crackerbox BJ26, 72A 1008W

UL-1 combo in the LSH, it uses even less power than your offshore, I note that its the only one not running a hydra ESC, is the UL-1 ESC the weak link that stops you propping up further?

Thanks again Hydromaniac, and I look forward to more data like this from others.

No the esc is not a weak link This is a hull I built and it is Very Light, The hull becomes unstable when over propped, This boat is quite fast and more stable with a bit smaller prop. This set up seems to give the best speed and driveability on race water conditions.

[Brushless55]

I see alot of people over at RCU think that the esc will only let so many amps though the system..
not really sure why ??

[Fluid]

My opinion is that not many who post there know much about FE boats. If they mean that an 50 amp controller will only let 50 amps through, then they are wrong. Any controller will allow as much as it will stand before it burns up.

Typically a 120 amp controller will have a lower internal resistance than a 50 amp controller, so the boat will go a bit faster with the better controller because of higher voltage to the motor. But when you add in the AquaCraft ESCs - which are clearly under-rated - the water gets a bit muddy.



.

[ozzie-crawl]

same with motors, i have seen them tell people if manufacturer gives a max amp rating thats all the amps it will pull.

[Brushless55]

ya it's kinda crazy over there