Joel Lagace

iTrader: (4)

That maybe the case but we cannot compare AVERAGE DISCHARGE VOLTS since there are various grades or levels of nihm based on the matching process. Also there has yet to be a AVERAGE DISCHARGE VOLTS curve shown anywhere for a lipo(if there out there i have missed it sorry). Im not sure why cuz its just a cut off that needs to be added to the discharger. Either way your saying that lipo is faster so its not like your looking for a weight advantage...

All we can use is nominal voltage. A 1.2volt cell is a 1.2volt sell, and 3.6volt cell is a 3.6volt cell, this is the only constant they are constructed as 1.2 and 3.6volt cells, Regardless some perform better then others. And what we have here is guys wanting a weight advantage simply because the cars looks like ass with lead on it or because they get wooped by nihm at equal weight and so instead of looking at why there car is slow they want a weight advantage.. We use these nominal voltage to identify the packs, its the only constant or known value we have by looking at a pack. If AVG Volts came into the mix we would have a sliding rule of weigh to match what grade of cells you where running



Someone earlier mentioned min weight was changed for 4 cell and should also be changed for 5 cell. Im 100% behind that, why? Because the everyone is running the same weight batteries. The lipo vs 6cell is different because one weights half of the the other, so to lower the weight rules would in effect give a huge advantage to the lipo user. The rules would and should drop weight when lipo is in the clear majority.

We have to assume a lipo is equal to a 6cell. After all thats what been the big claim in getting people to allow them to run side by side with nihm. The advantages were multiple cycles,no memory, no voodoo, just ready to run without the work. And that the .2volts was not to be an issue. So im accepting that, i just dont accept that they should get to run lighter cars because the technology produced a very light battery.


I am well aware that nominal voltage has nothing to do with the batteries perfomance on the track... the IR and average discharge voltage along with run time is what separates the good form the great packs. But we cannot compare that info its subject to quality of cells,brand of cells,quality of matching ect ect... The common denominator is the actually nominal volatage...

TimPotter

iTrader: (15)

Johan,

< take my moderator hat off >

You absolutely kill me. What I do not get is WHY. You guys push for Lipo acceptance ( justly so) , so you can run the Lipo tech against an already established ruleset. So the local tracks, and descision makers( ROAR too) try to fit this new tech into the current rules. Then you complain that your batteries are at disadvantage and want the rules CHANGED to suit Lipo better. The way we have worked with the differences in nominal voltage has been with weight. Thats how IFMAR, ROAR, EFRA.. etc. has decided to make it fair.

We have a well established set of rules, that are always changing, when Lipo becomes the NORM, and not the exception, the weight rules will have to change accordingly.

BTW, I would be willing to bet racers were faster with 5 cell ,even at the 6 cell weight . There is a flip side to why we went for 5 cell. Too much power and frying electronics...


Anybody got a taser ???

<moderator hat back on>

yyhayyim

iTrader: (26)

Hi Tim- about running the Lipo tech against the established rules...well, that's what I'm arguing here...as I stated before- I dont mind running my Lipo w/ 1525g 6 cell weight- if those are the rules then that's what we'll need to stick to at big events/FSEARA events, etc...that's doesnt mean its the right thing or the best thing for our cars, nimh or lipo.

EFRA changed to 5 cell in 2006 and after testing the new 5 cell format, decided to drop the weight accordingly, to enhance the perfornace of running 5 cell and lower temps, etc...now 5 cell cars are faster than the more powerful 6 cell cars and they run cooler and one hardly hears of thermals anymore or similar malfuctions- the weight drop is one of the big difference makers here...samething for 4 cell racing in ASIA and JAPAN.

My point is that the established rules at tthe time in 2006 needed to be changed to enhance the perfornace of the new cell count and power- testing was done and it was so concluded- to benefit the car and equipment- it has worked! The established rules were changed- after discussion and testing- we all know see the great benefits of 5 cell racing and many have switched to it in the US, too...

Well, before allowing Lipo to be legal in FSEARA racing, ROAR events, etc., I'm sure its members and directors noticed the pack is much lighter than 5 and 6 cell nimh packs- they also studied the packs and tested with them and studied its perfonance and how handle them- just like EFRA did, and the Japan Asian organizers did before they adopted 4 and 5 cell racing in their areas and accomodated the set rules to enhance their new cell count and weight drop in the packs....that's my point...that's all...I think that its something that needs to be looked at, I'd like to know if such tests were conducted by ROAR directors, FSEARA, and others, etc.?- I guess they added lead to the Orion 4800 packs and got he cars to 1525g and tested them and compared them to 5 cell cars running at 1525g and 6 cell cars at 1525g and came out convinced that after several tests, the Orion Lipo 4800mah pack/or 3200 pack was turning similar lap times than its 5-6 cell counter parts...based on such tests and comparisions- FSERA and ROAR, etc would them deem it fair to have the 1525g weight for all...if that's the case, Tim: I have no issue w/ this particular point. What worries me is that no such testing has been done- and thus put at a slight disadvantage in overall speed for lipo tech drivers for the reasons mentioned..

This is what has come up at Corals Springs, and for the racing planned in our area, we will revise the weight rules, based on our testing(months) of the Lipo tech and what we've seen w/ 5 and 6 cell- in mod...I have not tested w/ 10.5 or 13.5 equivalents.

More tsing has to be done, and its not easy to set rules for this stuff...but we'll try and see- even for 6 cell- most cars today with 6 cells dont are 40-50g under the 1525g weight...maybe droping it to 1475g overall- for all cars...we'll see.

RobertV

Don't tase me bro!

BullFrog

iTrader: (4)

Testing for our series races(FSEARA)? We tried as stated in my last post.We don't need tests we just follow the given guide line by Roar in this case for the min. weight. Since they currently do not make a 5 cell lipo pack I guess your going to have to add the weight. What part of this do you not understand. Since you don't race in our series and I know you can't just worry what you can run in Coral Springs.
Our series has lead the courtry in experimenting with new stuff or ideas. It's been that way since it was started in 1980.You can come on here and state your point over and over again but It's not going to make a bit of difference. The series has it's rules that we are voting on for 2008 and we have all accepted and discussed what we are voting on next month.
What ROAR does will be much longer. At least a year for all the stuff that's getting ready to hit the market.ROAR has never acted on quickly on new technolgy.You want quick race the masters class in the series.I started the Brushless and waited for someone else to say lipos.I believe it was Johnny G suggesting them.
This discussion really is over as you just want someone to say yes you can run lighter with your lipo battery.Oh by the way I'm blunt and to the point in a round about way- always have been.

John Stranahan

iTrader: (27)

YYhayim-since you dragged me in here against my wishes I thought I would respond. I agree with Glassdoctor.
Nominal voltage means nothing for us racers (it might be at 5 amp discharge).
Voltage at 20 amp discharge is somewhat helpfull for stock motor racing.
Voltage at 50 amp discharge might tell the story for mod motors but racer model discharge devices don't go this high.
There is plenty of published reporting on many brands of LiPo's in my two threads at 20 A, which you quoted. It is not absent like you say. I linked to a published discharge test at 95 amps for a LiPo I purchased recently.

I disagree with your premise that a ballasted LiPo is slower than NiMH in mod motor racing. If this was the case I would just switch to NiMH in your case. It is safer. Just because a buddy with NiMH passes your car does not mean your ballast is to blame. I have tested up to 4200's NiMH, not the new higher capacity.

There are two styles of LiPo batteries safer slow ones and faster more volatile ones. The safer slow ones may not have the edge.

Yes of course you should meet minimum weight until racers agree to change the minimum.

It is certainly not a crime to ask the manufacturer of your product so you can make an informed decision. The only reason to hide this is you are embarrassed about the source.

"in the end they just want to make it safer for all...they mean well I'm sure. They are just frustrated...cause thye are not getting their way? j/k"

This last quote of yours is especially abrasive. What is your intent. I don't have a "way" I am trying to get. I just test new stuff. It seems that you do have a way you are trying to get. No ballast.
John

Joel Lagace

iTrader: (4)

Consider this: 5cell dropped its weight for two reason, eveyone was running 1 less cell in that class. Not some... ALL racers in the 5 cell class run 1 less cell then in the 6 cell class. The other legitimate reason is they also dropped 1.2volts worth of nominal voltage. So why carry the extra weight if everyone dropped a cell and 1.2volts

The whole lipo debate cant even compare to what happed with 4 or 5 cell classes. Those where classes all there own each running less voltage... FACT IS LIPO anyway you want to slice it is 7.4volts and a nihm is 7.2volts. Lets for get that lipo is .2volts higher and just assume they are 7.2volts just like the nihm cells..... Why then should everyone drop weight? One reason to allow the minority running lipo an advantage in racing over nihm. Is it fair? no. And lest just say we did consider a weight drop for Lipos racing against nihm cars.. .What amount of weight would u want to run at? And how would u determine what is a fair drop? Currenlty nihm cars need to run lead to be legal (most cars do i know i have to add some)

To me voltage curves got nothing to do with it. IF BRAND XYZ released a new nihm cell that was slower then current packs would we allow those poeple to lower min weight because they choose to run slower cells?

I only really see 3 fair options here:
1)Let your club enjoy high number of entries in the 6cell or 7.2volt class and throw some lead on your car or

2)Split your clubs competative numbers up and create a stand alone lipo class that runs its own weight rules. (im not sure about u but adding classes to already low attedance hurts most clubs)

3) go with option 1 and wait it out a year as more and more guys convert over to lipo the demand to chane rules will increase. The reason the responce has been against lowering weight is currenlty nihm is the majority.

yyhayyim

iTrader: (26)

That post wasnt against you or about you John...I was just trying to explain to SMC's Jack Rimer where 8orbital and his insistance on getting their data and lipo source info comes from- since they were going at it for a while- the "they" is 8orbital and those like him who have posted similar demands from J. Rimmer/SMC on this thread- I meant to explain to him why they wanted to know this info, and so explained that IMHO its because they learned this from your threads and you ample testing and so they have also adopted this patractice and wish to know the SMC lipo info- I gree with your approace and support it also, and have always praised your work- you're one of my favorite fellows on these threads and hope it didnt come accross as otherwise...I apologize, John- hope this helps...

Now I have tested w/ orion lipos- 3200mah and 4800mah packs...w/ 4.5 and 3.5 BL motors...have you tested w/ the orion 4800mah packs? I dont belive you have, according to your posts- I could be wrong, so please correct me. These are the main packs in questions and the type that will be allowed in the FSEARA racing for 2008 alongside Nimh and BL.

My 1245g Serpent S400 reary to run w/ Orion 4800mah pack will be faster than a similar 1525g 6 cell or 5 cell nimh car. Temps are better for the battery and the esc and motor are also cooler (155-160F average in 5 minutes). We can hit 49mph down the straight on the radar gun, w/o the weights. When you jack it up to the 1525g weight, my car is noticibably slower, and barely hit 45mph on the radar, and temps do jump up to over 170F. Same for the others who have tested this for months now at our track. So in my experience, it is slower w/ ballasted so high w/ Orion packs, and the temps are higher and so are changes of thermals and damaging the packs due to high temps, especially in the 96F south florida weather. In the winter time the numbers will improve...Maybe MaxAmps packs will perform different or thunderpower? I dont know...I'll be testing soon w/ My MaxAmps 6000 HV cell and see what times we get. But adding all that weight on lipo equiped car the weight does make a big diference will make the car slower and add more stress on the car and get higher motor, esc, and battery temps. that's a fact...at least in my experience at my local track

Maybe try running your TC5 and Lipo w/o ballast weights, then at 1450g, and then at 1525g and see what results you get...

timmay70

iTrader: (5)

Has anyone given much thought to what would happen to the longevity of the cars that we race now if we started to inadvertently lightening the weight requirements of the chassis we use in racing? Right now I will have to add weight to my Phi in order to race at any sanctioned event. Amazingly, this is with the optional aluminum bits on it. If the minimum was raised to accommodate a minuscule perceivable drop in performance advantage, the chassis manufacturers would eventually start to take advantage of that and would in turn produce lighter chassis. This would eventually be at the costs of strength of parts. Then people would be complaining of fragile cars, and that the speeds are too much. Let's not mess with a system that works.

As far as your gear overheating, Nimh gear is subjected to the same stresses, and I don't hear these drivers complaining. Overheating of any electronics will do damage to them. It may not break them right away, this is a degradation in performance over time. Eventually, it will never perform up to standards. Some people call it browning, where some of the transistors die. The ESC still operates, it just is not able to hit it's high mark anymore.

We have a local driver that is running lipo 3200 packs. He has his good nights and he has not so stellar nights. He is running the steel battery plate in his JRXs and some additional ballast. Racing in stock foam carpet, he is on pace with his ability level when he uses Nimh cells, and this is with stock motors... Until I see back to back runs with someone that is able to run back to back not varying more than .3 over the runs will I believe a comparison of speed differences.

Btw, we don't enforce weight min., he chose to add the lead to his car. His biggest fear was changing the performance of the car according to how it was designed.

Keep the existing min.

undark

Can LiPo have the unintended effect of giving older, heavier cars new life since they can more easily make weight? Maybe nobody cares about old cars enough for it to matter though.

John Stranahan

iTrader: (27)

YYhayyim-Thanks for clearing that up.
Now if you need to add a bunch of weight to the car, the way to do this is to add more battery capacity in parallel. Performance will improve. You will be pulling power higher on the discharge curve so average voltage will be higher. Your batts will run cooler. Speed control and Motor temps will be higher. The latest LRP TC edition seems to have these speed control and motor temps under control. You might see a night and day difference in performance when you use that 6000 mA-h Max Amp Pack compared to the Orion pack, but you give up some safety. An 8000 mA-h LiPo might even be on weight. Now if the rules only allow the Orion packs then so be it. They are safer. There is another hardsided 4900 mA-h pack available from Flightpower in the latest Tower Hobbies catalog. It may perform better than the Orion pack, but it may not be as safe if it does perform better.

I have tested the Orion Chemistry but not their large super expensive pack. The chemistry is safer but the performance is just not there compared to NiMH or other Lipo's

or8ital

iTrader: (38)

Forgive me since I havent had a physics class in many years. But wouldnt the fragility of it lessen at the same time b/c there would be less weight hiting the wall at 30MPH? So maybe it would be a wash?

yyhayyim, Im actually not familar with this John guy but it sounds like he is into the safety of lipo as well.

timmay70

iTrader: (5)

It's all hypothetical at this point. How do we know where any one company will remove weight from? An example of this is X-ray. The bearings/hubs/axles in the T1FK were huge compared to the 05. They eliminated unsprung weight by making the hubs smaller and essentially using less steel (in the bearings/axles). Result was that my bearings would out-last the cars with the smaller bearings (RDX, 05, T2, 007), and the spring steel axles never wear out. There is a minor possibility that future cars will keep the beefed up (?) parts that they are currently running, but if history holds true, the performance advantage would be to remove the un-sprung weight. All speculation.

Fact remains, keep the weight levels the same, that might not ever become a problem - (that is still speculation now, isn't it - ha!).

rcgen

I have read this from the beginning twice now. You asked our opinion should lipos run the same weight as the 6c. Well, most on here posted in favor of the current weight limit. Running the lipo technology is new for the touring guys and is slowing gaining acceptance and an optional power source, so we must work within the guidelines. As more and more racer switch over I am sure the weight will be address.

At my local track we run a 19t touring class. We've allowed the 13.5 and 10.5 bl to run along with the 19t brushed cars. So far we've the majority of racers are moving towards bl. I am the only one who runs lipos and I had to plead my case to run it. New technology everyone doesn't know. Thankfully the touring guys I run with have a open mind. Last week another racer had a lipo pack in there car. So it slowing growing at our club level. We don't tech weight so and the motor's is a gentleman's agreement. So far there's really have been no real issue with a lighter running.

Our state race was the first time I ran my car at legal weight. I can say I actually like it. My PHI was balanced and handled better with the weights. Now if the weight limit was lowered, I would have no problem changing

I am basically saying the local club racing has to start the moving and setting guidelines, then it will move up. You've stated that your club has already been testing. Post some of the results. Show us what your club is learning.

Obtw, I choose to run brushless and a lipo for the convinence of racing. Also, I've noticed the lipos are at a disadvantage as far as the punch factor, but just knowing your pack will perform consistently and not worry about a cell dropping is all in the reward of finishing a race strong.

yyhayyim

iTrader: (26)

Like you said, the only pblm is they are approving only the encased type Lipo: like Orion, Trackpower, CoreRC, etc. I also prefer the cased Lipo- they are safer and neater looking.

So in order to run at sanctioned events, we all must abide by those rules- its the only way. That what the nimh fellows have been repeating over and over on the thread and that's what will be done...however, at our local track, thins will be different. We do have lots of testing and experience w/ TC and lipo power and how they run, and know pretty much at what temps is the best and weights works best on them. 90% of our club run Lipo's! They are done with nimh...only for state or national races.