I am looking at converting to a Lipo battery setup to save a little weight (WCM Full cage car). so I wanted to see if any one has any experience with them and what make/size batteries are best for quarter scale applications.

You going Electric Motor/Lipo Battery in a 1/4 scaler? Or just a LIPO to run the Radio Equipment?

(Would like to see a ELECTRIC/LIPO POWERED 1/4 scale car...LOL )

This is for the radio equipment/servo. I just want to replace my 5 cell sub C pack with a lighter 7.4 volt 2 cell lipo with a 6 volt voltage regulator. I want to get the lightest setup I can get and still make a 500 lap race.

the plastic cased Orion lipos are really light plus have the extra protection of the plastic case. (It doesn't offer a LOT of protection, but it does offer some)

The 3200 mah Lipos weigh approx 202 grams compared to a 5 cell 3800 mah NiMh pack which is about 350+ grams.

There are some non-cased lipos that are much higher mah's (Like the SMC's and Max Amps that I believe are around 5000 mah's...and I believe they are lighter yet (I've never used or weight them though)

..I was kind of hoping someone was going to try to build an electric motor/lipo powered 1/4 scaler.

I have been using lipo for our receiver and transmitter packs for awhile now. No problems and transmitter packs last 8+ hours before charging. Using digital servos we get almost 3 hours run time on our receiver packs for our off road cars. All of these are 2400mah protek 2cell lipo for receiver,3cell for TX. I use the Protek regulator for the receiver pack.

I have put the same setup for our Pro1 SP1 1/4 scales inside a Kyosho 777sp2 radio receiver box. The spectrum receiver and Lipo battery fits fine.

The pack I was looking at was a commonsenserc 2100mah pack that has an 8 amp continuous discharge rate. What type of run time do you get on your SP1. Do you think it could make a 500 lap GN race.

I am going to try my Lipo (7.4V 4400miah) pack in my car as a reciever pack this summer and am hoping that I won't need to charge it all day. I am also running a WCM cage car. I am sure that it is much lighter than the 5 cell pack because It is 50 grams lighter than a 4 cell pack that I use in 1/10 scale racing. I was able to run two 4 min races before it needed a charge in my 1/10 scale car. I did discharge it at 8.5 amps and it took just over 1 hour. My quess iis it will last a long time running the radio gear!!!...


Dave D

The pack I was looking at was a commonsenserc 2100mah pack that has an 8 amp continuous discharge rate. What type of run time do you get on your SP1. Do you think it could make a 500 lap GN race.

As I am new to the 1/4 scale scene and have not ran the NEW SP1 YET, I cannot honestly tell you. But We get 3+ hour run times on 2-digital servos in 1/8th scale offroad. I'm guessing you will get same or maybe longer on 3-analog servos for 1/4 scale. When this dreaded winter ever gets over I will be able to tell you to the minute though. LOL.

I am actually running 3 digital servos. Dave what is the brand Lipo you are running. I haven't been able to find anything close to 4400 that wasn't pretty heavy. Most were only about 50 grams lighter then the 5 cell pack.

I am actually running 3 digital servos. Dave what is the brand Lipo you are running. I haven't been able to find anything close to 4400 that wasn't pretty heavy. Most were only about 50 grams lighter then the 5 cell pack.

The one I have is a Common Scence (SP) in a hard case, It was $90.00 at a local hobby store!!!...

Dave D

I am thinking about the MAxamps 4000mah 20C Lipo pack. It is about 60 grams lighter then the commonsense pack without the hard case. I am mounting it inside a peice of polymar channel so I think it would be protected emough.

I needed the hard case so I could run it in my 1/10 scale car, I am sure without that it would be much lighter!!!...


Dave D

Dave,

What is the weight of your car with this battery. I only weighed mine once and I over 31 lbs with a 5 cell sub C battery pack.

Shaun

All of my 1/4 scale stuff is put away for a long winters nap at this time, in the spring I would be able to give you a total weight for my car!!!...


Dave D

What are you using as a voltage cut off?

What are you using as a voltage cut off?

If you are asking me I can run mine down to 6.4 volts without doing any damage to the cells!!!!...

DD

A receiver and servos will operate at 4.8v before they cut off. what keeps this from damaging the lipo?

The Lipo has a 3.2 volts per cell and the instructions say don't go below 3.2 per or 6.4 total or it will damage the cells. I think they can reverse polarity or something like that. There is a company that makes a in line cut off so when you get close to the low voltage you would loose throtle but no steering, seems like a good idea to me!!!...


Dave D

I have been doing some checking on the voltage that the LiPo puts out, most of the ones that we use are 7.4 V which is Ok in a 1/10th scale cars because the speed controler has a BEC that regulates the voltage down to 6v for the servo's and reciever. When using the LiPo in our 1/4 scale cars I think you would need to use a voltage regulator that would turn down the voltage to 6v or we are going to cook the recievers and servo's. Most hobby shops that sell LiPo batteries have the regulators because they use they in planes and Heli's...


Dave D