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  1. #1
    RC Racer
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    Switch from 7 cell NiMH to 2 cell LiPo (so 8.4v down to 7.4v)

    So, I'm considering making the jump from 7 cell NiMH batteries to LiPo. I'm running a Sidewinder SCT, trenchers and geared with a 9 tooth pinion and stock spur gear (for yard bashing and what not).

    Temps aren't getting too high so I'm ok with the voltage. I understand that the LiPo cells have good punch, but I don't want to go to a 2 cell pack if it's going to be slower than what I'm already running.

    What are your guys experiences with switching from NiMH to LiPo? I don't want to invest in the charger and batteries if I won't be happy.

    I also know that pretty much everyone is already on LiPo so you may never have compared to a 7 cell NiMH pack.

  2. #2
    RC Turnbuckle Jr. thedreadedend's Avatar
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    If your using a 7 cell nimh 8.4, the 2s lipo from a solid company will give you the same speeds in comparison. A fresh 2s comes off the charger at 8.4 so its about the same. The big difference is, your average nimh will loose that voltage very fast and within a few minutes you feel the power loss followed by a steady decrease till your done. A lipo will hold the "fresh charged punch" for longer, a lot longer. You still have some loss but it will sustain the punchy low end for most of the pack.
    I have run nimh for a while, I just recently switced to lipo. A high end top of the line nimh will perform like a lipo but also requires lots of attention and time. Lipo can simply go from truck to charger and back to truck with no waiting to cool down cause they don't heat up. I feel its a better way to go. All in all, you will not loose out on speed. You may gain speed with a high end lipo but not much. You will get more runtime and less waiting. You will not loose punch, it should be equel or more punchy and will last longer than the nimh punch from average nimh batts.
    I'm not a hatchet man! I'm a maggot!

  3. #3
    RC Racer
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    That explains it very well. Thanks a lot. I guess I'm not super concerned about the top end speed, just punch for around the yard and part. Right now with the 5000 mAh Venom I get about 25 minutes of run time and that's pretty good. I'd like to have maybe a little more run time (so maybe a 5200) and less hassle. 3S will be more than I need and I think would be overkill for what I do.

  4. #4
    RC Turnbuckle Jr. thedreadedend's Avatar
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    Venom is not very well known for their nimh. A 5000 should run your truck for 30+ minutes in the p4de. After reading your last post, I am sure that you will see more power from a trusted brand lipo. Ya 3s, its like running 9-10 cell nimh for punch with even more speed. Fun for crazy bashing and speeds but is well known for snapping stock drivetrains unless you have a loose slipper or upgraded from hex to diff out yokes lol.
    I'm not a hatchet man! I'm a maggot!

  5. #5
    RC Racer
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    My stampede came stock with a 3000mah 8.4v pack. When I put a 2s Lipo in there it was a clear upgrade over the stock pack in pretty much every category.

  6. #6
    RC Turnbuckle Jr. pavmentsurfer's Avatar
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    The only packs that can really give a good 2S lipo a run for their money is a Promatch 7cell.... everything else (for the most part) cant keep up in all the ways dreaded described. On top of all those good point, the 2S lipo will weight substantially less than a 7 cell nimh... and in a small truck, that does matter.
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  7. #7
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    Can someone tell me what the 20c,30c,40c, etc. means on the 2s lipos?

  8. #8
    RC Turnbuckle Jr. pavmentsurfer's Avatar
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    Its a rating of the packs ability to supply amps to the power system. The higher the C rating, the more amps the pack can supply. In a 4X4 asheck has shown that a 2S pack should really be in the 30C range if its a 5000mah or higher pack. In a 2X4 20C is enough... but a 4X4 pulls more amps so 30C is a good place to start.
    Pede, Summit,
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  9. #9
    RC Enthusiast
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    You will enjoy the 2s packs, and if yah want , u can gear up a little for more speed.

  10. #10
    RC Racer
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    Thanks guys, this is perfect. I have noticed that the Venom doesn't seem to run as long as other packs of similar capacity rating. I will start shopping for a LiPo charger and a 2S pack with 30c or higher and 5000+ capacity.

  11. #11
    RC Turnbuckle Jr. pavmentsurfer's Avatar
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    Venom Nimh packs are garbage... literally. They will not only not hold their rated capacity but they will overheat and often fail.

    Their Lipos on the other hand are pretty good packs. They perform well and are worth it if you choose to go that way.
    Pede, Summit,
    ERBE, Rally,
    Motley Crew, 1SQ

  12. #12
    RC Racer
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    I'm a bit peeved at the LHS for telling me the Venom NiMH was the way to go (I'm more peeved that I could have gotten a medium quality LiPo for what I paid for that pack). I'm finding that they really don't know that much about electric cars. I guess you live and learn and buy better stuff later

  13. #13
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    yeah, I bought a venom NiMh for my son's recently sold stampede and also for his summit vxl. The NiMh packs from Venom are total garbage. The factory Traxxas NiMh packs have way more punch and last longer. total was of money. But, as stated above, live and learn.

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