New ERBE owner with battery question

[razorxblade]

Would 2s lipo battery packs be a healthy upgrade from what comes stock with the truck? And if so do I
physically have to alter anything on the truck to accommodate the new battery packs power?

Thanks!

Andrew

[87 GN]

This is a good start..
Just don't buy no name Ebay batts...

MY BATTS:
2S 9000 x 28C = 252,000 divide 1000 = 252 amps
2S 8000 x 28C = 224,000 divide 1000 = 224 amps
3S 5200 x 40C = 208,000 divide 1000 = 208 amps
2S 4700 x 25C = 117,500 divide 1000 = 117.5 amps
^I run in my Summit.. ^ Requires proper gearing^


( mah x c rating / 1000 = amps)

The more amps the better / minimun of 120 amps.

The ESC will only draw the amount of amps it needs.

Higher the mAh the longer the runtime.
For brushless systems 8000 mAh about 45 min & a 5000 mAh about 30 min.
Times are longer for brushed systems.


Batts in series double the voltage:
2x 2s 20c 5000mah = 4s 20c 5000mah

Batts in parallel double the mah capacity:
2x 2s 20c 5000mah = 2s 20c 10,000mah.

A temp gun is kind of a must have.....

Hot motor + cool esc = under geared.
Cool motor + hot esc = over geared
Everything warm just right..

Motor ~ 180/190*F (82/88*C) maximum, ideally 140/160*F (60/71*C), temps can be 10*F higher inside the motor
ESC ~ pretty much same temps / Fan comes on @ 150*F (65*C)
Lipo's ~ 140*F (60*C) max, ideally 100/120*F (38/49*C).........

Besure to check sizing before you buy any batteries...

In time some batteries will become discontinued...


No particular order as to good, better, or best....

2S

With larger Lipo battery wires, you might need to - enlarge the exit hole on battery doors....
or run wires out the vents..

Direct Fit...........
2s GensAce 5000 mAh 40c
2s Gensace 5300mah 30c softcase packs
2s HiCountryHobbies/Billowy Power 5200 mAh 50c
2s Hyperion 5000 mAh 45C Soft
2s RC DUDE Power 5000 mah 35c
2S Sky Lipo 5000 mah 40C -- fit snugly
2s SPC 5000 mah 25C hard case
2s SPC 5200 mAh 40C
2s SPC 5400 mAh 50C hard case
2s SPC 6000 mAh 30C hard case
2s SPC 8200 mAh 30c
2s SMC 5400 mAh 50c
2s SMC 6000 mAh 28c
2s SMC 8000 mAh 28C Soft Case Lipo
2s SMC 9000 mAh 28C Soft Case Lipo
2s SMC 9200 mAh 50C
2s Team Orion carbon 7000 35c
2s Thunder Power 45-90c 5000mah
2s Over Sea's Co. 6000mah 25-50c
2s Traxxas 5800 mAh 25c
2s Traxxas 7600 mAh 25c


Mod's.............remove retainers & back out or trim screws if they extend into battery compartment
2s SPC 8200mAh/40C
2s Over Sea's Co. 30c 5000 mAh soft - Extend Batt Door Out
2s Over Sea's Co. 5200 mAh 5.2 Hard Case - Trim Batt Door For Wires
2s Over Sea's Co. 5000 mAh 5.0 Hard Case - Trim Batt Door For Wires
2s Over Sea's Co. 5000 mAh 30C hardcase

[razorxblade]

Thanks for a quick response! That guide is really going to help. Now do I need to change any of the gears to accommodate the
2s lipo batteries?

Thanks,

Andrew

[87 GN]

Start with the supplied 54 spur & 18 pinion.
I run 2/2s 9000 mAh 21/54 at low 50 mph, all temps are good.

[Brewers74]

The lipos will put a smile on your face...just take it easy or you will have axle & differential failure

[razorxblade]

Okay great I found that part, now this is how much of a newb I am.... How do I got about swapping out the old gear with the
54/18?

Thanks,
Andrew

[87 GN]

http://traxxas.com/forums/showthread...=1#post4920527

[razorxblade]

Thanks for the link man! I think I can manage that gear swap out

Andrew

[razorxblade]

Just ordered some of the Traxxas 2S 2-Cell 7600mAh batteries off of Amazon. Should have them sometime next week. I also ordered up a dual charging adapter for the 2S lipo's, so hopefully that'll get me using my revo faster. I didn't realize how long it takes for the batteries to charge. Is it normal for a 7 cell 8.4v 3000 mAh battery to take over an hour to charge?

[Biggie7871]

^^ You're gonna love the traxxas lipos! I have the same ones you just ordered and a pair of 5000mah 3s. I also bought the dual charging adapter for both sets and they normally take between an hour to a hour and a half to charge.

[razorxblade]

Thanks for the info! What are the run time differences between the 3S 5000 mAh and the 2S 7600 mAh?

[87 GN]

higher the mAh the longer the run time
the more cell (higher voltage) the more power & speed
C Rate is discharge (punch)
5000 little over 30 min
8000 well over 45 min

but you are comparing a 5000 3s to a 7600 2s.
You can't get an 8000 3s to fit the Revo with out major mod...

Start with a good set of 2s batts then decied if you need a set of 3s.
like 5000 mAh 40C........ 200 amps

[randy0050]

i would not run the stock batteries unless you make sure the low-voltage setting is correct

[Biggie7871]

Yeah like 87 GN said its kinda hard to compare the run times between the two sets especially since I bash more with the 2s and the 3s is mainly for speed runs. I get about 30-40 min with the 5000 and I get anywhere between 45-60 min with the 7600's. It really depends on how you drive the truck.

[razorxblade]

I guess it would be difficult to tell the differences between the two for run times. I'm looking forward to the power increase and
the extra run time from the 7600's though.

[razorxblade]

I just got my 7600's in today. Everything seemed to be going good, but when I went to set the amps for the battery my
charger, the EZ-Peak Plus only goes up to 6 amps. Does this mean I can't fully charge my 7600 mAh batteries I just got?

[87 GN]

no it just means it will take longer to charge.....you still charge to 4.20v (full)

[razorxblade]

Thanks for the reply. Man the 2S's last so much longer than the stock batteries! They seem to be a bit faster too, however I'm
Already getting the want for more power. Luckily I just found out that there's a rc shop about five minutes from me that
specializes in traxxas rc cars and they have a big selecetion on pretty much anything I need to maintain/upgrade my truck with. I'm gonna play around with the 2S's for another week or so, then I'll probabaly take the plung to two 3S batteries. I'm thinking
I'll swap out my stock pinion to a 18t one to work with the 54t gear that I just installed. Any thoughts On how well that setup
Would work?

[LaTuFu]

The stock pinion is 18T. What do you have on their now?

[razorxblade]

Oh I thought it was 16 for some reason. If its stock then its the 18t right now. Since I put the 54t gear in should I change the pinion to accommodate the smaller 54t? And if so, to what size?

[87 GN]

before you get a set of 2/3s try ............... 21/54 on 2/2s is low 50 mph
not heat issues......

[razorxblade]

21 you say? Excellent I will try that out and let you guys know how it goes!