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Old 07-31-2009, 03:08 PM   #1
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Default Weight diff recieverhump Lipo / Nimh???

Hi guys.

Ive been using a couple of Reedys 1600 Nimh humps in my Losi 8ight and are not complaining about performance but Im considering changing to Lipo to reduce some weight.

If I compare one of my 1600 Nimh humps to a similar (is Lipo 1600 about the same) Lipohump, what would the weightdifference be?

Is the runtime about the same or would it be better with a Lipo?

Im thankfull for any help at all since this Lipostuff is new to me.

Thanks.
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Old 07-31-2009, 03:17 PM   #2
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Quote:
Originally Posted by harleyrules View Post
Hi guys.

Ive been using a couple of Reedys 1600 Nimh humps in my Losi 8ight and are not complaining about performance but Im considering changing to Lipo to reduce some weight.

If I compare one of my 1600 Nimh humps to a similar (is Lipo 1600 about the same) Lipohump, what would the weightdifference be?

Is the runtime about the same or would it be better with a Lipo?

Im thankfull for any help at all since this Lipostuff is new to me.

Thanks.
rx packs have now available lifepo4 6.4 volt and no regulator needed ,safe,longer life span,runtime is better,can overcharge and low voltage cut off.

the difference in weight between life,lipo and nimh is

lifep04 about 70 grams lipo about 75 grams depending on manufacturer
nimh 125-130 grams so there is a big difference nealy half the weight

i hope this helps you.
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Old 07-31-2009, 03:18 PM   #3
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My 1500mah 2S lipo pack + voltage regulator are around 65grams together.

with BLS servos I can go 2 hours.

with same mAh lipo your runtime will be about 25% higher
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Old 07-31-2009, 05:21 PM   #4
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With most newer cars, the battery is placed towards the front of the car. I believe this design is to get more weight on the front of the car. This aids in steering. I wouldn't be so concerned with the hype of weight so much. A smooth trigger finger and being a smart driver will do more for you than taking weight off the car.
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Old 07-31-2009, 06:05 PM   #5
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I just weighed a lipo vs. nimh, Lipo was 1500, nimh was 1600. Here's weights:

Lipo:
grams:74
ounces: 2.6

Nimh:
grams: 121
ounces: 4.3
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Old 07-31-2009, 07:35 PM   #6
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it all depends on brand and mah....saying lipo weighs XXg's and nimh weights XX's is a Bogus comparison....in general tho lipo's are lighter.
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Old 07-31-2009, 07:43 PM   #7
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Thanks guys for your help.

So Im looking at around 50-60 grams difference.

The reason for me thinking about the change is the design of the Losi 8ight. Everything is so centered in the car that I was thinking it would be a good thing to lower the weight in the batterybox since its so far out on the side of the chassi.
Is the Losi 8ight designed for Lipo or Nimh as far as weightdistrubution in the car is concerned?

Would I feel the difference? Maybe not, but I would know that I did what I could to help the car perform better.
Am I wrong and just wasting time and money.
Yes I know that practice, practice and more practice would help the most but I like the feeling of having the best stuff so I know its just down to me and not the equipment.

Thanks for your input and everybodys opinion counts so keep it up.
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Old 08-02-2009, 05:34 AM   #8
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I switched my rc 8 over to lipo and will never consider anything but lipo.The weight savings is nice and the power is incredible. I have never ,ever been happy with the nimh batts.
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Old 08-02-2009, 06:23 AM   #9
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Quote:
Originally Posted by Joey Platinum View Post
I switched my rc 8 over to lipo and will never consider anything but lipo.The weight savings is nice and the power is incredible. I have never ,ever been happy with the nimh batts.
Hey Joey, How's that Caster Storm Fleetwood Edition holding up!

Did you know you can lose that giant regulator of yours now! Turns out that Hitec 7955 servos and the Spectrum Dx3r Reciever your useing can handle a 2 cell 8.4 volt unregulated lipo easilly. I've seen others up here running that setup now. Was big news to me! I thought your running 7955's right?

I've got two 7955's on the way, and my hitec rx should handle the Lipo unregulated. I think I'll be picking up a Spectrum Dx3r after this season is over, my M8 has seen better days.

8.4 volts going to a 7955 should be about 350 torques in .12 seconds.





Nihm stinks, I can't stand cycleing batteries. Can charge my Lipo after every qualifier if I want to.

A 800mah lipo is tiny, weighs barely more than my RX, and plenty of battery for a 15 minute main.

Last edited by Zerodefect; 08-02-2009 at 06:25 AM. Reason: the sparrows are flying
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Old 08-02-2009, 07:02 AM   #10
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Quote:
Originally Posted by COBRARACING View Post
rx packs have now available lifepo4 6.4 volt and no regulator needed ,safe,longer life span,runtime is better,can overcharge and low voltage cut off.

the difference in weight between life,lipo and nimh is

lifep04 about 70 grams lipo about 75 grams depending on manufacturer
nimh 125-130 grams so there is a big difference nealy half the weight

i hope this helps you.
Who makes the 6.4 volts lipo?
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Old 08-02-2009, 08:46 AM   #11
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Isn't A123 a lower output 2 cell battery?

I think Maxamps has some but they're kinda big.
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Old 08-02-2009, 08:55 AM   #12
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I switched from a 1600mah NIMH pack to a 2100mah Lipo. Its only 1oz lighter but knowing I can make it through most race days or being ready to make a couple bump ups if necessary makes it worth it. I figure I can easily make 2 hours on the lipo pack.

I use a Spektrum receiver and Hitec 5955 servos so I can run unregulated. The servos are noticeably faster with the lipo and I'm certain they have quite a bit more torque too but Im not going to risk my fingers to find out.
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Old 08-02-2009, 09:51 AM   #13
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PTP ,I ran the 5955 without regulator for a while & had no problems but was told by a friend that works at Hitec I was lucky & should not have done that. Upgrade to the 7XXX servos if you want no regulator. Unless your 5955 post was a misprint & you ment 7955.
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Old 08-02-2009, 10:21 AM   #14
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You better read post #3 in the link here for "Ask Hitec" to be sure.

Unregulated 7955, 7965?
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Old 08-02-2009, 02:29 PM   #15
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Quote:
Originally Posted by air8 View Post
You better read post #3 in the link here for "Ask Hitec" to be sure.

Unregulated 7955, 7965?


there are also posts from Hitec Reps that claim the 5955 is ok for lipo.....im not going digging for them...but they are there.
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