how is this?

[Serum]

I just had contact with BK over this issue, they also sell the IB3800's, and they claim that the GP3700 is the best for the highamp MT trucks..

The GP3300 is a great cell, it kept the highest voltage on a heavy load (100A) one cell is able to give a rough 100 watts. (voltage @ 100A is about 1V, which is pretty amazing for those absurd high amps.) according to the information BK gave me, the GP3700 would be a tad better. those IB3800's are not recomended for 70A + applications.

And according to Mike's experiences, the IB3800 has got a bit more punch.

I'm going to get a new set GP3300's and those IB3800's.. (the 3700's don't seem to fit the gmaxx chassis)

I should get me an eagletree data recorder.. I'll warm up my girl for one..

@awqut, what cells did you use with you former setup?? you need to know that a BL setup can't be any stronger than the power your cells can produce! a 16 cell setup can't deliver more than 1600 watts (with perfect cells that is)

[toby]

so ibc3800's are better perfroming then gp3300?

[Serum]

No, according to BK, the 3300's are 100A rated, and the IB3800's 70A.. With a rather hot setup (7XL on 18 cells) it will for sure take more than 70A!

[toby]

i am so confused on which cells to get, 3300 or ibc 3800? I AM CONFUSED :s

[Rtsbasic]

You can't really go wrong with either. Look at it this way, the 3300 will give you maybe slightly more power because the higher peak amp draw, the 3800 will give you more runtime, and be more punchy for longer because the extra capacity.

[coolhandcountry]

Find a price on your batteries and let that help as well toby. I like the gp 3300 and the gp 3700. I do seem to get a little more out the 3700 as far as punch and run time. The gp 3300 is a good batery. I have never tried a ibc 3600 and 3800.

[aqwut]

My former setup was Dual brushless with 18 cells(36 cells) each... and 24 cells each (48 cells)

I was thinking of gettin' two 22.2Volt 8000 mah, lithium cells.. (12C) 96 Amps continuous.. which is roughly 2100 watts.. but I'm gettin' two packs.. so I guess that's over 4000 watts of battery juice.. Should be good for my 2280.. I want full power... Nothin' goin' to slow me down but a tree or parked car.. hahahaa

[aqwut]

Robotcombat sells GP 2600 Sub C's... they rate it at 80 amps continuous.. 3300's are 45Amps continuous....

The Sanyo C's are also 80 amps continuos.. both the 3000mah and the 3600mah...

I'm gonna get some of those GP2600 sub C's....

I'm pretty sure the guys at robotcombat knows their sh*t.. :) ALways learing something new in the RC world..

[aqwut]

Well if price is a problem toby.. just buy Loose unmatched GP3300s.... can you guys really tell the diff between matched and unmatched packs... I really can't tell the difference, but the price... :)

I remember I had these really cheap $$$$ GP3300 unmatched rainbow packs, which I bought from ebay..

I got three 6 cell stick packs for $100 shipped from hong kong back then.. and they performed just as well as my FineDesign Packs... but half the cost..

[coolhandcountry]

I can see a little bit of difference. If I was to race matched, not racing a good deal on good batteries matched or not.

[Rtsbasic]

Thing is matched batteries give you only a small bit more punch, but they keep giving it till the battery gets very close to dumping, unmatched cells will start to drop off eariler. I notice this in the last couple of laps racing my truck (GP3300 cells).

Unless you discharge/equalise your cells after every couple of runs they'll be unmatched by the time you've used them 50 times, bear that in mind.

[Serum]

Yes, once every 10-20 times of use, give them a 1/10th C and 1C 2-3 cycle treatment! they will thank you for that!

[Rtsbasic]

I don't really do that..I just fast discharge mine after every run to 0.9v/cell, and equalise all the cells just before recharging every 3-4 runs. My 8 cell packs are taking in ~4000Mah and peaking at around 12.2-12.3V, so can't be that bad. Coming off the charger around 40-45C which is fine.

[Serum]

How do you discharge them at .9 volts per cell? or is it 8 times .9= 7.2 volts? or do you really equalize them with .9 volts per cell? and how do you get 1.5+ volts in your cells?

[Rtsbasic]

When the charger peaks on the cells each cell is approx 1.52-1.53v (using a 4mV/cell delta peak cutoff).

I have an old Mtroniks 10 amp discharge device that does 4-8 cells, I set it to discharge to 7.2v for an 8 cell pack.

I use a discharge tray (LRP Concept) to equalise the cells down to 0.6v/cell. This is a 6 cell tray so I do 6, then move the cells up 2 and do the remaining two. I use a Novak Millenium as a charger with a Pro-Peak 13.8v/20 amp power supply.