what are lipos=too?

[Chrislong]

Hi Peetbee, the 4800's should fit fine then, the most you'll have to do is lift the cell posts with some washers and longer screws - if atall.

The 4800 does have longer runtime, but that really is not a factor as a pack only needs to last 6 minutes at the very most. The main thing with the 4800 is that it will have more punch as per the calculations below:

1C of 4800mah = 4.8
therefore 25C of 4800mah = 120 Continuous amps
20C of 4800 = 96 Continuous amps

20C 3200 = 64 Continuous amps.

I can't recall if the 4800 is 20C or 25C, but I do know the 3200 is 20C. As you can see, the 4800 will give more ampage than the smaller packs whicher C racing, and therefore you are likely to have more power than you'll need. When i run the high capacity packs I do motor down to a 7.5R Novak and the cars are as quick as 5.5R Novak when with cells.

[sparrow.2]

That's all highly technical, but when you consider that a good pack of 4200's is able to put out 35-40A even the 64A continuous out of a 3200 lipo will be more than sufficient, as there is only so much power an offroad car can put down at any one time without wheelspinning or doing a somersault backwards.

Touring cars and pro10 are going to have trouble because they manage to empty a 5200mAh lipo in 5 minutes and actually pull peaks of around 200A going onto the straight. Crazy quick but they do have their lipos go up in flames sometimes.

[Gayo]

I used an Orion 3200 lipo at Kampenhout on my X-6, with a 6.5. I never had so much power on a 2WD, enough to lift the front tyres everywhere on the track, even at the end of the straight, so for me 3200 is more than enough.
Oh, and mileage was good too, around 10 mins before the first fade of power. I never went to the lipo cut-off.

[peetbee]

Thanks Guys, I run 7.5Rs in both cars and have 4100 nimhs now, by the sound of it the 3200 lipo should be comparable in terms of punch.

If that's the case I can't see me needing the 4800, the extra run time would be nice only to avoid having to recharge between every heat.

[Chrislong]

Originally Posted by peetbee

Thanks Guys, I run 7.5Rs in both cars and have 4100 nimhs now, by the sound of it the 3200 lipo should be comparable in terms of punch.

If that's the case I can't see me needing the 4800, the extra run time would be nice only to avoid having to recharge between every heat.

Oh I would recharge after every run. I would not risk over discharging the pack.

But remember, if you run twice, you'll need to charge it for twice as long so you might not make the 3rd run. Whereas after 1 run you should be able to just recharge it and make the 2nd run, recharge then the 3rd run.

There is no memory effect whatsoever, except they do remember that they are mullered when you muller them. LOL. But no harm in recharging from partial, no need to discharge, store with any amount of charge in etc. Just don't flatten them, or store them almost flattened.

Chris

[peetbee]

I get two races out of a pack of nimhs at club as I charge them up the night before, I can then swap packs and do another two races, so don't need to take a charger, etc with me. I was thinking that with the cutoff on my GTB I'd be ok, or shouldn't cutoffs be trusted?

At competitions I do charge between heats so would need to get more packs.

Would you say 3200 lipo is a match for 4100 nimhs in terms of punch, (but not duration)?

Sorry about all these questions, I couldn't seem to find the info elsewhere.

[Chrislong]

3200 Lipo will be more powerful than your 4100 cells, and more duration too considering you are charging your cells the evening before. Remember cells self discharge and have losses due to getting hot through a race, and Lipo does not, only gets mildly warm during a race.

If your having 2 packs, and only doing 2 runs on each to then recharge at home - using a Lipo cutoff GTB, you should be fine I reckon, especially considering you can do it with 4100 cells. Id be tempted to recharge them sooner after this, then leave them charged for a week until the next meeting you attend.... rather than leave them again until the evening before the next meeting, as they may be borderline flat.

Chris

[peetbee]

Thanks Chris, it all sounds great to me, think I'll be ordering soon, just need to find the cheapest trakpower stockist!
I'd charge them on arrival at home and then they'd be ready for the next week, result!

[sparrow.2]

I used these. Click Great cells and cheap as chips. They alslo come in 4000mAh 25C flavour for just a little more.

[Jonny_H]

Originally Posted by sparrow.2

Touring cars and pro10 are going to have trouble because they manage to empty a 5200mAh lipo in 5 minutes and actually pull peaks of around 200A going onto the straight. Crazy quick but they do have their lipos go up in flames sometimes.

1) Are you guys still running Pro10??

2) How do you get enough traction with a Pro10 to get anywhere near dumping? My RC10L3 (190mm Pro10) always had to be turned down to make it driveable, even on carpet with additive.

[sparrow.2]

Originally Posted by Jonny_H

1) Are you guys still running Pro10??

2) How do you get enough traction with a Pro10 to get anywhere near dumping? My RC10L3 (190mm Pro10) always had to be turned down to make it driveable, even on carpet with additive.

I wouldn't say Pro10 is huge here but there are always a couple of nuts at it.
Apparently with the newer foams the cars have insane amounts of grip and effectively lap faster than 1/8th scale nitro flat track cars
Nice cars out too. The car in the picture is a Hatzenbach. A small-series complete work of art by a couple of nuts here in Germany. Made to order only and a bit dear too




A bit offtopic but hey

[Jonny_H]

Coooool...

I've really got to find time to get my L3 up and running again.

[peetbee]

Originally Posted by peetbee

If that's the case I can't see me needing the 4800, the extra run time would be nice only to avoid having to recharge between every heat.

Now of course I didn't listen to myself and have just received my shiny 4800 saddles!!
I've got the diggety design posts on order for the B44, but does anyone know where can I get longer threaded bar from to let me to re-use the thumbscrews in the B4?
Thanks