acejinx

I just sold my nitro sv27 and bought the e-sv27. Now I'm deciding on batt's, it seems to me that with the extra voltage running 14 cells would be much faster. Is this the case?

Unrelated but an prop suggestions?

SV27dayton

You will get more speed but you will also get more heat. It's adds more weight so the best bet is to go lipo if you can swing it. My best bashing props are a octura x642 and x440/3. Both have been thined down and I took every effort to not remove diameter from them. I've gone 41.3 on 12 cells with the 440/3. Any more prop than these two with 14 cells and you have to start thinking about your ESC. You should read the SV27 cooling thread if you want to go fast. I bumped a thread within the past week or so called SV27 owners that contains links to all the useful threads about this boat. Have fun.

madmax22

check these lipo's out, also this charger! These are what im going to run (but in a different boat)!
http://www.hobbycity.com/hobbycity/s...idProduct=8357 <lipo's
http://www.hobbycity.com/hobbycity/s...lancer/Charger <lipo charger

asupervee72

beware of overly inexpensive lipo. you really do get what you pay for in my opinion. 25 c 4000mah sound like really nice numbers though, let me know if you get these and how they are, 30 usd is a great price for those numbers. looks like a nice charger to me plus it has the deans plugs already attatched so you'd be good to go

Stinger9d9

I already have a couple pairs of PolyRC lipos, so I decided to pick up a couple of these to try out for some sport running as well:

[link]http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=8578&Product_Name=ZIPPY_Flightmax_5000mAh_2S1P_20C_[/link]

At this price, you (almost) can't go wrong. All the customer reviews are positive. When I previously dealt with this site for some suspiciously cheap 80amp ESCs with positive reviews, they turned out to be excellent.

I won't be pushing these packs too hard, and definitely won't be racing with them, so I'll take my chances. If I wire 2 of these in parallel in my sureface drive Hammer, it'll run for almost 1/2 hour!

ozzie-crawl

havent tried the zippy flightmax but i run all my boats on zippy h or zippy rhino real good batterys at a good price

acejinx

Wowwy, Wow, Wow! I have had great luck with hobbycity, the prices are to great to believe they are good, but they are great. I'm excited to try the 'hard-sided' I didn't even think to look, so thanks for the suggestion.

Now two questions:

1. What will happen if I get these things wet, you know I will.

2. Does anyone know if you can set the Aquacraft esc to a voltage cutoff?

Thanks Again,
Ryan

acejinx

I'm sorry, it's late, that last post wasent all that clear. I'll proof read better in the future.

SV27dayton

My understanding of the AQ 45 amp esc is that it does have a cutoff but it's based on the voltage it initially sees. So if your lipos are fully charged the ESC will cut out (completely) at the propper point (a percentage of the original voltage). I don't like this situation so I will get a lipo shield if start running lipos in my SV.

LENYLOW

If you do decide to go with 14cells instead of lipos disconect the bec on your reciever and run a receiver pack
you will also need to upgrade the water jacket to the ose one as the motor will get hotter, but it will fly.

acejinx

I think I'm going to go with the Lipo's. I really like the idea of it being lighter, we usually race on a short track and I think it will accelerate and corner better. I am concerned about them getting wet though. Thanks for the suggestions so far, and please let me know how those lipo's work on your boat.

WakeBoardnBash

DO NOT buy the hardcased lipos that were linked in the 2nd reply to this thread.


Compare the feedback of the hardcased lipo's to these-
https://www.hobbycity.com/hobbycity/...idProduct=8578


Get the soft packs.
You will be much happier as far as quality goes.
I havent had a single issue with these batteries and i own 12 total.
I also run these in 2 different SV's

acejinx

Thanks for the soft pack suggestion, have you gotten them wet? Dumb question, if they are in a boat they will get wet. Do you do anything special to dry them out, or do you just let them sit in the sun?

WakeBoardnBash

Thats another problem..

Any and all Moisture will be obtained inside the hard case that is surrounding those lipo's suggested earlier.
If your lipos do infact get wet, i suggest unplugging them immediately and letting them air dry.
Not in direct sunlight, more in a place that is breezy, set them in front of a fan if possible.
Only wetness i have experienced were a few drops of water on the outside of the lipo battery it self usually from removing the hatch.

SV27dayton

What is it about the hard case that makes them less desireable?

Stinger9d9

It's not all hard case packs that are the issue, but if you read the reviews for those particular packs, they have issues with the quality of assembly (not necessarily the quality of the cells), issues that seems to be hidden by the hard case.

Apparently some of the solder joints on those packs are poor, and the connectors on some packs don't even line up with the holes in the hard cases!

The other packs (the 5000mah ones like the ones I bought) have nothing but 5 star positive reviews. They must be assembled better.

As far as using hard packs in a boat, well, it is more weight (if only slightly) for no performance gain, and if the packs get wet, the hard cases may actually hold the moisture inside the pack more than shrink wrap.

In the end, the 5000mah packs are more capacity (obviously) than the 4000mah hard case packs, and they are essentially the same price.

For the record...I've gotten all 4 of my PolyRC lipo packs quite wet, and I just let them air dry between runs...never a problem.

SV27dayton

Thanks Stinger,
Always a pleasure to hear from you. I think these will be the first thing to push the big cat. May have to cycle them through the SV a few times first tho.

acejinx

Awesome, thanks for all of the info. At 29 bucks a piece if I do toast one by getting it wet it won't break the bank. I will be running in fresh water so conductivity shouldn't be too much of an issue.

I'm amazed that you haven't got your batt's wet yet, if I am behind someone and coming into a patch of rough water I just can't let go of the throttle. Physically impossible. I've tried.

I'll say something if getting the soft packs wet destroy them.

SV27dayton

My boat's up-side-down all the time but it's sealed well enough that it's floated for an hour bottom-up with now water in side. If your transom is sealed and your hatch taped and your batteries are well secured you should stay dry.

Stinger9d9

My super cheap 5000mah Flightmax packs showed up today. I charged them up (they were about 2/3 charged with they arrived), and took them to the pond.

They worked great. Not quite as much punch as my newer (10-15 runs old) Poly RC packs, but a LOT more punch than my older (bought them used after a season of racing) PolyRC packs.

The slight difference may have been due to the difference in weight. While these packs are NOT heavy, I'm comparing one of these 5000mah packs to one 3200mah PolyRC pack that is a fair bit smaller. The boat I'm running them in is super light, and a hundred grams here or there is slightly noticeable.

As far as getting them wet, I'm using my old water jacket from my SV27 on this boat (my 35mph Hammer) and it leaks like no tomorrow. The water pickup in the rudder is drawing in water with MUCH more force than that jacket was designed to handle, so the boat has 1/2 a cup of water in it after each run.

I have a real water jacket on its way, but in the meantime the batteries in this boat always get a good rinse, and these ones, like all the rest, put up with it just fine, no issues at all.

Here is a pic of one of the packs after I just started to charge it. It turns out I don't need that balance connector adapter board to plug the pack into my blinky balancer either. The connector matches up fine. I am planning on taking 2 of those boards and wiring them together so I can charge both of my Flightmax packs together as a single 4S pack.

SV27dayton

I will need to do something similar. I do not have a balancer and will need one as soon as a purchase packs. Can you recommend a balancer, possibly one that will balance two 2S packs or possibly 2 4S packs at the same time. I have a Superbrain 979 charger but im under the impression that the balancer functions completely independant of the charger. I'm on the bottom of the lipo learning curve.

chummer

I am going to order these as soon as they are restocked. Does anybody know how long they usually take to restock? I don't have a lipo charger yet so I have to buy that as well.

I was thinking of this one http://www.greathobbies.com/producti..._id=THP610C+++

It has JST HX balance connectors so will this work with those lipo's? I am new to all this lipo stuff and I find it a bit confusing compared to Nimh. Any help would be appreciated.

asupervee72

i was worried about my batteries getting water in them so i put clear caulking at the ends where the shrinkwrap wasn't sealed then i just wrapped the ends in electrical tape, dont know if it was necessary but it gives me peace of mind, i wouldn't run lipo on the aq 45 amp esc without a lipo shield, think of it as a $20 investment to save you hundreds on lipo batteries, the owners manual didnt mention anything about lipo and the esc when i read through it so i deff wouldn't trust it, i got a nice lipo shild that is about the size of a quarter and was really easy to put on, there is a link to the site i got it at in one of the sv threads, i think its the battery one, the pics are before and after of the battery mod

Stinger9d9

The multiple types of balance connectors are the single most confusing thing I find when trying to buy Lipo packs.

The Astroflight Blinky balancer I have plugs directly into many different types of lipo connectors and...prepare to be even more confused...it does NOT go between the charger and the balancer.

The Blinky plugs into the balance plug, while you plug the pack into the charger like a regular nimh pack (through the deans or 5mm bullet connector), then the blinky scrubs extra voltage off of whatever cell is slightly more charged to keep both cells the same level of charge until the pack is done.

What little I've learned of charging Lipo packs started with this video:

[link]http://www.youtube.com/watch?v=k4JsOgwbubc[/link]

Then, while asking if two 2s packs can be charged as a single 4s pack, CadillacETC2000 posted this diagram to show how to wire them up to do so:
[link]http://sincitytrader.com/Uploader/files/6/4S1P_from_two_2S_Packs_Adapter.ppt[/link]
Remember, the 2 packs have to be absolutely identical before trying this.

There are also pre built boards out there for doing the same thing, but I don't know if they would work with my Blinky balancer.

acejinx

I love my astro blinky. It's cheap and I've used it for years.