What batteries for P Limited Rigger?

[Andy Brown]

What is legal for IMPBA? What is a good "budget" battery for racing? Will be using AQU 7011 ESC and AQU 7001 motor.

Thanks in advance.

 

[HOTWATER]

Hi Andy, I am using Hyperion 4S 35C 5000 packs for my P-Limited riggers...not budget packs, but good quality, ecspecially for racing...just my opinion....

-Kent

 

[HTV Boats]

http://www.allerc.co...y-c-3_4_93.html

http://www.bananahob...s-1323-ctg.html

http://www.hobbypart...nsace60c4s.html

http://performancerc...s.com/page8.php

Here's some sites to compare. Remember "C" ratings are sometimes manufacturers hype. I have 25C Hyperions that perform as well as some cheap 40C's. I have heard some good things about the Dinology batteries from some west coast record racers, and will be ordering some myself to see if they stack up with my Hyperions. Hope this helps. L/W/H can vary between manufacturers and rule of thumb for me is 16oz = 4000ma.

Mic

 

[HOTWATER]

Also, RCLipos....free shipping and 10% off with code (4U10)...

 

[Chilli]

Andy the IMPBA has no rules as far as mAh capacity for FE boats. And it doesnt even have a national P-Limited class. The P-Limited rules are done on a club and district level. The higher mAh capacity and C rating, the easier it will be on your battery and equipment. I've been using the Hyperion 45C 5000's and the three year old packs are still running strong in heat racing. I have run the cheaper 45 Turnigy Nano Techs from Hobby King. They perform well for a year or two but thats about it.

 

[Andy Brown]

Thanks guys! I knew the Hyperions were good and I figured some companies may have "Hyped" the C ratings. So it all boils down to "Pay me now or pay me later". I think I'll just step up to the plate and get the Hyperions.

 

[HOTWATER]

Good choice.....

 

[lohring]

Andy

The most important factor in a battery is internal resistance. The low cost batteries usually have more than the expensive packs. However, this years low cost packs are as good as the expensive packs of a few years ago. The best thing about the P limited boats are that they make great propeller dynos. Everything else is so close and the runs are so consistent that propellers are everything. Where I race, propellers are often changed and/or tweaked after every heat. The equipment runs up to the edge of failure, but motors still last several seasons. The fastest boats don't always run the highest cost batteries.

Lohring Miller

 

[Chilli]

Build quality of the pack and customer support are also very important. FYI-Thunderpower cells have run pretty strong for me, but I have had the ends of the packs crack and I have also had ballance taps go bad on more than one occasion. I've never had a problem with the Hyperions. Just go easy on them the first couple runs and give them a storage charge at the end of the weekend and they will give you many years of service.

 

[Andy Brown]

Thanks Lohring and Mike!

Yes Lohring, I have contemplated building electric for a long time just for the purpose of prop testing.

 

[Jim Caldwell]

Mark F provides Dinogy lipos, I have hammering on them and they are just as good if not slightly better than my Hyperions.

dinogylipos.com

Did I mention they are 1/3 cheaper!!!

 

[T.S.Davis]

MAH will depend on who you're planning to race with too. If you're allowed to leave the shore at 20 seconds and then pull to the middle you could get by with 3300's if you buy quality cells and your boat runs light on it's pads. 3750's would be perfect IMO. If you're going to do a couple heat em up laps and a cool down lap you'll want the 5000 mah packs. Bad thing about the bigger cells is that you have to propel the extra weight.

Dynogy packs can be had at http://performancerclipos.com/ Pretty good bang for the buck. I overdischarged mine down to 3% on a 180 amp setup and they survived.

 

[HOTWATER]

In our District we have to launch at 45 sec. on the clock to make sure everybody gets in the water....I will easily burn 3750 out of my pack after 5 laps with no cool down....alot of times 11% or 12% left on the 5000 pack...lol! (a couple heat em up and cool down laps in FE? huh?!)....a lighter boat/pack may do well at SAW's but does not mean a thing in heats...better a bit more weight than not enough.....5000's easily for any P-Lim. racing.....

 

[longballlumber]

I have been using the GrimRacer Speed Packs for 2 seasons now. Performance wise, they are just as good as any of the other packs out there. I've had plenty of success racing in our club events and events I've traveled too also. Most of my packs are now 2 seasons old, and I won’t hesitate to run them again next season.

http://www.aquacraftmodels.com/accessories/lipo-packs.html

Later,

Mike Ball

 

[lohring]

It mostly comes down to math (sorry). A data logging speed control helps. Since Castle isn't making a 100 amp water cooled ESC, I suggest an uncooled ICE 200 lite. I've seen one record 300 amps before it shut down without damage so it will be lots tougher than the P limited motor. That way you can see what the current draw is and from that determine how much battery you need. Read Electric Power Basics for more information. The power draw (volts times amps) is also a great propeller yardstick. The prop that goes fastest with the least power is the most efficient.

Lohring Miller

 

[Grimracer]

I have been using the GrimRacer Speed Packs for 2 seasons now. Performance wise, they are just as good as any of the other packs out there. I've had plenty of success racing in our club events and events I've traveled too also. Most of my packs are now 2 seasons old, and I won’t hesitate to run them again next season.

http://www.aquacraft...lipo-packs.html

Later,

Mike Ball

I would like to add... We have a dude here at work and all he does is test batteries.. (I would go NUTS doing this day in and day out) Never the less we have YET, to see ANY LIPO perform over 50C. To date we have NEVER been able to prove any lipo over 50C. Having said this right now Im not sure they exist regardless of what they say.

Grimracer 5000 packs ARE 40C no bones or BS about it. I was not going to PUMP numbers for the sake of "marketing". If the race and record results are not enough to prove performance to ya.. choose another brand!

BTY.. One single 2S 5000 Grimracer lipo IS the fastest battery in the world.. over 100mph at 7V... THAT IS PERFORMANCE! The data log on that battery was like.. add more hot sauce to the dip brother.. I aint yet starting to sweat!

Grim

 

[T.S.Davis]

Lohring has a point. Math don't lie.

3300 x .80 = 2640mah of fuel

2640 over 90 seconds = 105.6 amps average

The motors can pull more than that but not forever. That's not to say a particular boat doesn't want the extra weight.

I figured it out once upon a time but I think a 50 mph turn is somewhere around 4G. So that extra half pound of battery weighs an extra 2 pounds coming off the apex. So your 5 pound boat weighs 20 pounds at the apex. A 4.5 pound boat weights 18 pounds. Guys need the extra mah because their boats are heavy. There is no single right way to do it really. If the boat wants the weight there's zero problem with doing it that way.

It's a balancing act. If it's not a known setup the 5000's might be the safer choice. I haven't run a 5000 pack in LSH in years. Don't need it so why carry the weight. I ran a TP3850 for that.

Kent, what do you do for 45 seconds? 3 laps?

 

[HOTWATER]

We start to launch at 45 sec.....One take your time wide mill lap ...end of the back straight at 10 sec., then then the start. We run P-lim hydro and p-lim. tunnel combined with the nitro guys (those guys will most likely do 3 or 4 or more mill laps)...

So you run 3 FE mill laps? Why?...sorry...not at all trying to be rude here, just don't understand...

BTW...we run Aquacraft UL-1 motors and esc's with our P-Lim. setups in D.12...pretty sure D.13 does the same....

-Kent

 

[T.S.Davis]

We don't. We do a one lap mill. With a spec rigger that could take 15 seconds. I was wondering what you did with the extra 35 seconds. We're in the water at 30 but I always give guys grief if they are taking off at 30 seconds. If they're in the back straight at 20 seconds they're going to cause a mess at the start because they'll be doing 3 mph with boats coming at them running 50mph.

So you do one slow lap while the nitro guys are blowing through multiple laps at 3/4 throttle. I'm suprised that has caused any mayhem.

..........sorry. After I typed it I had a mental image of the mahem guy from the Allstate comercials popping his head out of the water with a helmet painted like a turtle.

 

[HOTWATER]

The Allstate image..lol! We're also in the water by 30 sec. No mayhem really...works just fine for us...by then everybody has a lane, but you never know...it is racing....