Different 2.4V Mod

[Admin]

I took a different approach to get 2.4V into my Blue GTR. I used a small CPU Clock Battery from Jaycar instead of the extra cell. This is really a battery pack with two NiMH button cells inside. The dimensions are 15.5mm x 12mm, a bit bigger than the standard NiCad, but it fits in the well with some small mods !

Results ? As for the two cell mod…. the car is quick ! But I suspect even quicker acceleration wise since this battery is lighter than two standard cells. Plus, it all fits under the body, so unless you look closely, you cant tell its a 2.4V mod.

The downside compared to two cells is run time, although we are still talking over 5 minutes with a 3.0 motor ! Of course, this is really only for drag racing, I can hardly keep it in a straight line !

Here is the link to the cell :

See http://www.jaycar.com.au and look for Cat. No: SB1608

[Admin]

Any chance of some pix, Shonky?

I found this pic of the cell itself at http://jaycar.com.au, but I’d like to see a snap of it in your car if possible?!

The specs are enticing to say the least (reposted here as the long URL that you posted did not work:

Part number SB1608
Voltage 2.4V
Capacity80mAh
TypeNI-MH
Size(mm)15.5 dia x 12H
BrandVARTA
TerminalsSolder type
MTBFUp to 6 years at 60 degrees
1,000 cycles
NotesContinuous overcharge capacity
Low self discharge
Interchange compatibility with Nicads
PriceAUD6.95ea

Good find!!!

Derek

[Admin]

No pics yet derek….. I was really keen to get the battery in the car and run it. I even butchered the car a bit and I reckon I could do it better the second time around.

I will probably rebuild it on the weekend and hopefully snap off the details then ! I forgot to mention that the range improved as well with this mod !

Generally however, the GTR seems to be a slower car. I have a yellow Lancer also and did an experiment. Ran the 3.0 in the GTR(prior to 2.4V mod)and 2.2 in the Lancer, which was a close match. Swapped the motors and gears between cars and the Lancer (now with 3.0) made a significant gap !

The GTR has a silver controller while the Lancer’s is orange. I suspect the drive electronics were improved in the later model Lancer ? Have others had this experience ? I intend to mod the Lancer for 2.4V in any case and I expect an even quicker result ! I will also design a stand alone charger to properly charge the 2.4V cell for better runtime and maximum performance !

[Admin]

Shonky, how are you charging that battery now? I tried something similar. I used NiMh button cells individually and soldered two of them toegther. They were only 60Ma and didn’t last 2 minutes. Then, I charged it on my desktop charger and never got more then a minute of run time and it got worse each time I charged. I think maybe my charger is too powerful?? Any Suggestions. I’ve got a bunch of NiMh button cells left I’d like to try something different.

[Admin]

I am using the standard charger for the moment. I took apart the controller and looked at the charging circuit, it is really simple and the 2.4V cell can becharged with it, but more time is required (I did about 3 minutes).

The standard cell is only 50mAH and my 2.4V is 80mAH, assuming that the current drain is similar under 2.4V operation (this will depend on the car electronics), we should expect longer run times.

I dont think the standard charger is at all good for the battery and it wont do long term at all, to charge these things properly, you need a constant current source circuit. The design can be found on the web, I am going to build a stand alone charger around this.

When I am done, I will be sure to post the results !

[Admin]

hey how do u use this mode

[Admin]

15.5mm sounds like a AA.Were you able to get it tofit inside the chassis?

[Admin]

there is also a 1.2v cell that is 280mah at jaycar.

could have your car running for quite a while!!!

it is a little larger than the 3v lithium batteries (cr2032) and would require a bit of modification to fit into the body of the car.

the battery is 25dia x 8.8mm

i hooked one up outside the car, but it looked weird so i took it off.

i also tried a 1/3AAA 3.6v battery rated at 43mah, but the runtime was too short.

[Admin]

Hello guys,

I just picked up two packs of the 3.6 V batteries from Jay Car…….Man the thing freakin flies now !!

Run time is in the 5 or six minute range – pretty small capacity at only 43 MAH – howeve rit is so damned quick that you cant really concentrate on it for longer than that !!

This is in fact my bit charg A – oem car that I use to perform “experiments” on – that is about all they are worth in my opinion – sounds harsh – however I highly recommend getting the “REAL DEAL” when it comes to these cars 🙂

The great thing is that once you take the tabs off the cells – it plonks straight into the BIT with no mods :

The only realproblem is the fact that you cant put the clear plastic cover over the electrics……not a real drama though – I am just using some clear scotch tape at this time – until I can work something more appropriate out :

Just have to play around with gearing now…… a bit slow to start with this standard oem set – even though it will pull the front wheels off the deck if you go from reverse to forward !! Have to do something about that paint job…….

One interesting point is that I no longer have steering problems with the car – obviously because of the increased voltage to the coils……

Next project will be a nice 2.4 conversion in my other oem – this should provide the best of both worlds – more speed – and better steering and less weight than the standard battery…..

I still wish there was a 1.75 volt cell that dropped straight in – this would fix everyones steering problems !!

Hope this helps or inspires some of you guys.

Cheers

Darryn

My web page: http://www.darrynsretrorc.rtox.com

[Admin]

thanks darrynsretrorc, thats great.. i think i visit to jaycar is on my list for next week..

cant wait to try it out.

[Admin]

I looked at the 3.6v cells while I was at Jaycar but thought the combination of high voltage and low capacity would cause havoc on the electronics and runtime (respectively)…. perhaps I was wrong !

That 3.6v cell is quite a good fit, my 2.4V is not quite as comfortable, but it certainly has the capacity ! I think we need a way to bench mark the results… perhaps a mini equivalent of the 1/4 mile run ?

[Admin]

The mod is definately not for the faint of heart – the car is pretty much unctrollable really…….

So far, (10 or so full charges), there have been no problems with the circuit board – seems quite happy – however I could give no guarantee’s on that – or howlong the motor will last as it is TRIPPLE the standard voltage. I am not particularly worried though – as I am not a big fan of the OEM’s – so it is no great loss to me really.

I will try and give an update occasionally on how it is performing or destroying itself.

I think the 2.4 volt mod by removing one of the cells is going to be the best though for general use in a relatively large area…..

Cheers guys

http://www.darrynsretrorc.rtox.com

[Admin]

Theoretically:

When you apply double the voltage across the same resistance, it takes twice the amount of current I=V/R. This means that when you double the voltage to the bit motor or steering coils (these are both resistance constants)it takes twice the current which means if the original battery was 50mah you would need a 100mah battery of double voltage to run the same amount of time. I would expect shorter then stock run times with a 80mah 2.4V battery then a 50mah 1.2V battery.

Again, this is theoretical. I’m interested in actual data

[Admin]

Actual data is something that is going to be difficult for any of us to put down really – as there are many factors to incorpaorate when “timing” a scale 1/4 mile time etc etc……Best thing I can do at the moment is use my Bit Char G digital lap counter – and time my runs – however – again there is reaction time and many other variables.

Run times are in the 5 to six minute rage – so it is not too bad……however you theories are correct – as anyone with a little electrical experience knows…..thankyou! 🙂

Cheers

Darryn

My website : http://www.darrynsretrorc.rtox.com

[Admin]

V=IR rarely applies in these types of situations fora fewreasons :

The entire circuit may be voltage regulated.

The motor current actually varies with rpm and load.

The motor drive electronics will introduce some voltage drop and the output stage could be limiting current to the motor under these conditions that it is not designed for.

Not to mention that the battery itself probably isnt being charged properly and we cant guarantee that it represents its full capacity or even voltage.

But who cares really…. its fast and it runs for 5 mins ! So its cool.

[Admin]

Iam having trouble finding a U.S. site for the 3.6V NIMHbattery, the closest I have found is this one:

http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CTLG%5F004%5F000%5F000%5F000&product%5Fid=960%2D0481

Would that battery work? It is 3.6V 60mah NICD. Does anyone know of a radio shack part number for the 3.6v NIMH one pictured above in the thread? or where i can get it in the U.S.? Also how much does it cost to ship something to the U.S. from Jaycar and how long does it take?

Thanx

Rob

[Admin]

there should be shipping info at the jaycar website.

http://www.jaycar.com.au

[Admin]

prabbit on your dual battery setup can you use telephone wire? also is soldering required or can you tape it with some electrical tape

[avoid the noid]

hi i was wondering if anyone knows where to get the 3.6v battery i want to put one in one of my cars and see how it does i cant find one on radioshack

[Admin]

http://jaycarstore.webfactory.com.au/index02.ws4dyou can get a 3.6v there

[avoid the noid]

thanks but i live in america not australia thanks anyway tho

[Admin]

at jaycar all it says about shipping to USA is: Oversease shipping (P.O.A) $0.00. what is P.O.A? and why does it say it doesnt cost anything?

[Admin]

P.O.A is price on application…. because their system is not smart enough to calculate international shipping charges, so they will have to weigh what you buy and figure out the charge.

I am surprised you cant buy these batteries in the US, most of them are really used for keeping the clock running on your PC motherboard.

[Admin]

Hey darrynsretrorc

Any news about a different charger for the 3.6V battery in the car?? I brought my battery yesterday from Jaycar, and the car flies, but i only get really small runtime, so i think a new charger is needed 🙂 Are just using the normal charger at the moment? Did you do anything to it? Does your charge light come on when you charge it ??

Also Shonky i brought one of the 2.4V like you said, just wondering how you got it in there lol … any pics yet ?? Would be greatly appreciated

Any other information about these 2 batteries (SB1606 and SB1608) and how to charge them would be great, and also any other batteries that will fit into these little cars. At jaycar, these are the only 2 batteries i could see would fit without having to do too much

Thanks guys, will wait for your replies 🙂

[Admin]

darrynsretrorc, shonky ?? Where are you guys ??

Anyone else been trying to get other batteries in ??

Any input will be appreciated 🙂

Thanks

[Admin]

Coolsurfer, you can use telephone wire if you want to. I used solid telephone wire for the terminals on my battery because they were ridged and I could bend them just right so I can snap my battery in and out. If you don’t want to solder you could used tape but I would recommend using stranded phone wire as it’s more flexable and won’t break after bending if a bunch of times. Any wire will work, really. The current is so low and we’re not really worried about frequency gain like on the antenna so you don’t have to worry about what wire is used for the dual cell mod. Anything will work.

Good luck. Show us what you come up with!

[Admin]

how u guys get ur bits to work? I’ve done the two battery mod, but my car only runs about 5 seconds on full throttle then it just get slower and slower. Please help me!

[Admin]

Sorry about the silence… got too many project on at the moment, bit-char has taken a back seat.

Barrelll, still no pics, but basically I had to cut the support post for the standard battery, bend one of the terminals down, then solder a wire to the other one and connect it to the top of the battery.

My install was not neat, I want to revise it, but everything still got under the shell (just).

As for charging, I have bought the components for a simple charger and I plan to build a standalone specifically for the 2.4v car. The circuit for the charger can be found at :

http://www.dprg.org/nicad_charger.html

The charger is important for ensuring the car runs for as long as possible and retains full voltage throughout the cycle.

-Shonk.

[Admin]

Hey

Well i made my own charger, using the way by the ones made by K.I.T.T and the guysat http://www.questformadness.com/

It included buying a 4 AA battery case from jaycar (http://jaycarstore.webfactory.com.au/index02.ws4d– Product ID PH9200)

Using the instructions at QFM i took apart one of my Bit char-g controllers and unsoldered the charging component and then soldered those wires to the Battery case.

I put 4 AA batteries in the battery case (giving it 6V of charge) and put my bit char-g (with the 3.6V battery in it) on it and charged it for a minute… and it FLEW, wheelies heaven !! Although the charge only lasted about a minute, i then put it on for about 3 mins and got about 2 mins of run time

More tests still need to be done, the low run time could be due to the battery, as i have been stuffing around with it trying to charge it on the normal charger, etc. I have a new battery so i will chuck that in there, charge it up and let you guys know what the results are

Again if anyone has found any other batteries that will fit in the cars aswell as the one im using (3.6V, 43MAH from jaycar – SB1606) please let us all know, especially if we can find a battery that has better run times with the same performance .. hehe

Well if anyone has anything to say about these battery mods, lets hear it !

[Admin]

The charger I will build simply limits the current of the charge to a constant rate, thus looking after the battery a little better. These fast charge cycles are not that good to start with, but I anticipate that connecting those fourbatteries to the car is probably one of the worst ! With that configuration, the intial charge rate will be very high as the cells increase in voltage and then it will ramp off. Constant current charges simply look after the cells and limit the maximum current applied !

-Daz.

[Admin]

Shonky,

Let me know when youv done your charger, and how to do it .. lol .. i want to look after my batteries (@$12 each .. can be pricey!!)

Thanks!

[Admin]

Just added that 2.4v cell to my yellow Honda S2000 (40mhz). Took me a while to fit it in, and it’s sure as hell not pretty, but the car is damn fast.

Managed to snap one of those really thin wires while i was in there, but soldered it back together.

It doesn’t wheelie, but turning may cause it to flip onto it’s side or back.

I also modified my controller so that it charges at full voltage (3v – from the QFM site)

[Author]

Posts