R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric On-Road

Reply
 
Thread Tools Search this Thread
Old 04-06-2010, 07:27 AM   #1
Tech Elite
 
Joel Lagace's Avatar
 
Join Date: Feb 2002
Location: Ottawa, Ontario, Canada
Posts: 2,619
Trader Rating: 4 (100%+)
Default Lipo $20 vs $100 = same results?

Ok Nihm has been dead around my club for a few years now. And at first we all migrated from what ever matched nihm pack we had to that matchers LIPO pack. The assumption was if they have the best nihm surely they have the best lipo...

But unlike nihm it seems that you dont need to cycle and match 10000cells to find good packs. IT would seem that just about any lipo can do the job these days.

Infact at our offroad club i would guess that just about 95% of us are using a 20-30$ hard pack.... The on road club is perhaps still using the "Brand" name packs but the more i look around less people are dropping 100$+ on a lipo pack..

Having done more then a few back to back runs with "BRAND" name packs and my new 20$ packs i must say at least in offroad there is very little difference if any at all..

Whats going on in you clubs? Are guys still spending 5x more then then need to? Has Brushless motors helped?

I had asked for a magazine to step up and do a LIPO shoot out and develope a LIPO Dyno of sorts or simply use the old standard of cycling packs on a Turbo matcher to rank who's packs really live up to there claims?

Anyway post your thoughts.. Back in the nihm days we had many FANBOYS but for good reason most of the time. No one would dare run loose cells... it was more then a sticker... it was ontrack performace. Im just not seeing that with lipos these days..

Not complaining.. i think its great to buy a 20$ pack and basically never take it out of my car. Just race peak race peak.. at 8amps no less
__________________
"Without Rules its just Backyard Bashing!"
www.rcottawa.com
Joel Lagace is offline   Reply With Quote
Old 04-06-2010, 07:32 AM   #2
Tech Champion
 
abailey21's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2007
Location: SoCal
Posts: 5,216
Trader Rating: 36 (100%+)
Default

http://www.bigsquidrc.com/li-po-batt...final-results/
__________________
K.C.C.O.
abailey21 is offline   Reply With Quote
Old 04-06-2010, 07:39 AM   #3
Tech Elite
 
Joel Lagace's Avatar
 
Join Date: Feb 2002
Location: Ottawa, Ontario, Canada
Posts: 2,619
Trader Rating: 4 (100%+)
Default

Thanks gots some reading to do...
__________________
"Without Rules its just Backyard Bashing!"
www.rcottawa.com
Joel Lagace is offline   Reply With Quote
Old 04-06-2010, 07:54 AM   #4
Suspended
 
Join Date: Feb 2009
Location: All over the place
Posts: 2,933
Default

With the globalisation of manufacture, I guess there's a handful of places where Lipo cells are made. QC decides then what goes where. Brand name batteries probably pay top dollar to secure the cells they want and make sure they are within the parameters, the rest goes to lesser companies and so on all the way to the rejects which end up in cheap packs. This being my picture I believe you can be lucky and get a good cheap pack but it's not going to be phenomenal, and you can't be sure the next identical one you buy is going to be as good. The price then reflects the parameters imposed by the company making the packs, not the one making the cells.

Sure, on the other hand technology is so good that it is likely the top product will not be much different from the bottom one (bar perhaps backyard made crap) as is the case in many other industries.
niznai is offline   Reply With Quote
Old 04-06-2010, 08:38 AM   #5
Tech Champion
 
robk's Avatar
 
Join Date: Aug 2001
Location: Macho Business Donkey Wrestler
Posts: 7,556
Trader Rating: 22 (100%+)
Default

In offroad you will never see the limits of the battery unless it's 1/8 electric. Even in on road, you don't see the limit outside of mod. You will see the lower resistance of better batteries in on road, and that helps lap time, but you don't tax the battery C rating wise.

If you race paved oval, yeah, you'll get better results with the best batteries. Offroad is traction limited, so you can't get all that power to the ground anyway.
__________________
A mutually re-enforcing cascade of failure

"Failior [sic] crowns enterprise." Robert Goddard

I-Lap Scoring Systems http://www.rclapcounter.com/
robk is offline   Reply With Quote
Old 04-06-2010, 09:10 AM   #6
Suspended
 
Join Date: Feb 2009
Location: All over the place
Posts: 2,933
Default

Quote:
Originally Posted by robk View Post
In offroad you will never see the limits of the battery unless it's 1/8 electric. Even in on road, you don't see the limit outside of mod. You will see the lower resistance of better batteries in on road, and that helps lap time, but you don't tax the battery C rating wise.

If you race paved oval, yeah, you'll get better results with the best batteries. Offroad is traction limited, so you can't get all that power to the ground anyway.

With the new ESC software on the market you will see the difference very soon in on road between a good battery and a lesser one. Even between identical batteries you will see any tiny difference immediately (running them in the same car). I have logged my car and it's pulling over 55Amps under hard acceleration and I only race 17.5 with a mild setup (no aggressive boost/turbo ramp)
niznai is offline   Reply With Quote
Old 04-06-2010, 10:08 AM   #7
Tech Adept
 
Join Date: May 2006
Location: sunny Cancun, Mexico
Posts: 214
Trader Rating: 1 (100%+)
Default

Quote:
Originally Posted by niznai View Post
With the new ESC software on the market you will see the difference very soon in on road between a good battery and a lesser one. Even between identical batteries you will see any tiny difference immediately (running them in the same car). I have logged my car and it's pulling over 55Amps under hard acceleration and I only race 17.5 with a mild setup (no aggressive boost/turbo ramp)
I doubt it, not on 1/10 scales as mentioned before. A typical cheap 5000Mah pack has a discharge rating between 20c and 30c, that's becoming pretty standard now, at 30c that pack can take a 150Amp continuos discharge, event the cheaper 5000Mah 20C packs will take 100 Amps now, much higher than your esc.
On a 1/10 on road car there is just no way you'll have a 150Amp continuous draw since the vehicles are so light, the new lipos are just so much powerful...
Rufus2000 is offline   Reply With Quote
Old 04-06-2010, 10:59 AM   #8
Tech Addict
 
Tubaboy's Avatar
 
Join Date: Jun 2005
Location: Riverton, WY
Posts: 582
Trader Rating: 9 (100%+)
Default

Here is the difference between a lesser pack and an SMC pack. Same car, same track weekend.

Cheap pack Fast Lap Times... 20.106, 19.545, 18.025

SMC pack Fast Lap Times... 18.077, 17.817

The first heat with my SMC, I had traction rolling issues.

This is in VTA. Where supposedly C rating should make a hill o beans difference using a 21.5 brushless motor on a GTB with a fixed FDR.

I also suffered a brown out with the cheap pack causing a couple of laps to not be counted with the cheap pack. (Transponder wasn't getting enough power!!)

Paul
__________________
www.wyomingrc.com | www.wyomingmodelerspark.com
Tubaboy is offline   Reply With Quote
Old 04-06-2010, 11:08 AM   #9
Tech Regular
 
Join Date: Jun 2008
Posts: 275
Default

i think c-rating is just a measure for comparison not an actually tolerance. high c-rating batteries have supposedly lower internal resistance which mean more power/voltage at any current level. BUT i read somewhere that it has come to a point that a little extra resistance can keep battery temperature up in the optimum area since a warm pack maintains voltage better than a cold pack.

Quote:
on the other hand technology is so good that it is likely the top product will not be much different from the bottom one (bar perhaps backyard made crap) as is the case in many other industries.
i think this is true and in traction limited racing, like 2wd off-road, the premium you pay for a high tolerance pack will not pay you back since off-road has inherently inconsistent perfomance (aka one little wheel slip can cost you the .05 seconds you better battery may have gained you).
benben10 is offline   Reply With Quote
Old 04-06-2010, 11:33 AM   #10
Tech Master
 
pejota's Avatar
 
Join Date: Apr 2008
Location: Vero Beach, FL
Posts: 1,020
Trader Rating: 11 (100%+)
Default

The better questions might be, what is your level of skill and where are you racing?

If you're a top 5 club racer, then save yourself some money.

If you're top 5 in your country or the world, then you'll want top of the line everything.

At some point, our own skill level limits any gains made from top of the line equipment. I'm not saying to get the cheap stuff but allocate your budget to the things that will help you get around the track on race day.
pejota is offline   Reply With Quote
Old 04-06-2010, 12:11 PM   #11
Tech Elite
 
Joel Lagace's Avatar
 
Join Date: Feb 2002
Location: Ottawa, Ontario, Canada
Posts: 2,619
Trader Rating: 4 (100%+)
Default

Quote:
Originally Posted by pejota View Post
The better questions might be, what is your level of skill and where are you racing?

If you're a top 5 club racer, then save yourself some money.

If you're top 5 in your country or the world, then you'll want top of the line everything.

At some point, our own skill level limits any gains made from top of the line equipment. I'm not saying to get the cheap stuff but allocate your budget to the things that will help you get around the track on race day.

Very tru. Im just a club racer. ITs been a great change to see over the last 2 years.. seeing guys in the club dropping 400$ for 4 hot packs to stay in the game to most of us just running 20$ lipos. the difference is so slight its not worth it.. Of course running offroad helps make the 20$ lipo an option... I suspected that the onroad racers would find it different..

Tubaboy: No offence but you posted very inconsistent lap times with both packs you used.. u had a 2 second spread on your cheap pack and a .3second difference with the SMC.. Your suggesting your faster and more consistent with the SMC? I'd rather see your top 5 and top10 print off from your AMB timing just saying your stats are not valid...
__________________
"Without Rules its just Backyard Bashing!"
www.rcottawa.com
Joel Lagace is offline   Reply With Quote
Old 04-06-2010, 12:24 PM   #12
Tech Master
 
Razathorn's Avatar
 
Join Date: May 2009
Posts: 1,972
Trader Rating: 2 (100%+)
Default

I'm building a 1/8 electric and the $220 reedy 40c 5000 is 51 grams lighter than the cheap zippy and turnigy packs that I would need to run. That was my motivation. Picking the lighter pack and a lighter motor (shorter shaft vs longer shaft) along with a few light weight parts saved me over a QUARTER POUND total on my car.

I was going to get a turnigy or zippy until I consulted weight. I'd rather spend $150 more up front and have my buggy be much lighter.
__________________
AE B6D / AE B44.3 / AE RC10WC / AE RC8B3
Razathorn is offline   Reply With Quote
Old 04-06-2010, 02:36 PM   #13
Tech Addict
 
Tubaboy's Avatar
 
Join Date: Jun 2005
Location: Riverton, WY
Posts: 582
Trader Rating: 9 (100%+)
Default

Joel, you are correct. When I look at the #'s, I consider it the same. The biggest difference for me, was the 2 laps I gained when I switched to the SMC battery, which was due to more consistent driving... here are the #'s below: (6 minute qualifiers)

3200 20C batteries
Heat 1: 18 Laps @ 17.77
Top 5 Average: 20.314

Heat 2: 18 Laps @ 10.53
Top 5 Average: 19.624

Heat 3: 18 Laps* 1 lap was not counted due to afore mentioned brown out issue. So really it could read as 19 Laps. However, would not affect Top 5 Average. 19 Laps @ 9.24
Top 5 Average: 18.456


4700 28C SMC batteries
Heat 4: 20 Laps @ 17.04
Top 5 Average: 18.092

Main: 20 Laps @ 18.46
Top 5 Average: 18.044

This track is setup right before the event, so it takes a while for the groove to come in. Heat 4 was just overall a very consistent run. I had 1 bobble, and flipped the car upside just one other time. Another factor that may throw off the times, is that qualifier #4 and the mains are run on Sunday, giving the track even more practice time, along with a night for the TC to soak into the track giving it more bite.

Also, since this was VTA, I didn't mess with the setup at all during the weekend on this car. However, my notes show that the car pushed in heats 1 and 2, started to come around on Heat 3, in heat 4 it was just a bit to much grip (started traction rolling) and by the main, the car had so much grip I would traction roll at will if I didn't handle it carefully on the high speed corners. Overall, the car and its setup is a perfect example of what happens to a track over the course of a weekend.

Overall, it could be a fluke. But not having the brownout issue is enough for me.

In the other class I ran at this event, my lap times were almost dead even all weekend long. (1/12th) Granted, I have a better feel on racing 1/12th than I do VTA.

Heat 1 30 Laps @ 15.496
Heat 2 30 Laps @ 13.081
Heat 3 31 Laps @ 5.791
Heat 4 Broke
Mains: 30 Laps @ 6.394

Overall, buy what MAKES u happy. That's my bottom line. If the $20 lipos make you happy that's great. If the $80 lipos make u happy, awesome.

The one item I will state that is lost in the cheapy vs. name brand argument is customer service. If my SMC or Reedy pack craps out I can send it back to them for customer service.

If a cheap pack goes out, well you can buy another cheap pack. So maybe not so bad, since you can get 4 $20 packs compared to one $80 SMC pack.
__________________
www.wyomingrc.com | www.wyomingmodelerspark.com
Tubaboy is offline   Reply With Quote
Old 04-06-2010, 03:45 PM   #14
Tech Fanatic
 
Ffejdat's Avatar
 
Join Date: Apr 2005
Posts: 904
Trader Rating: 5 (100%+)
Default

The other thing to consider for some racers and tracks is, if the pack is Roar legal or not. The cheap packs are usually not, and charging them like the first poster said is not legal (1c rate) last I heard.... Do I care, no, not most the time, other people might.....
__________________
Ahhhh, I could'a got a falcon!
Ffejdat is offline   Reply With Quote
Old 04-06-2010, 04:11 PM   #15
Tech Elite
 
Joel Lagace's Avatar
 
Join Date: Feb 2002
Location: Ottawa, Ontario, Canada
Posts: 2,619
Trader Rating: 4 (100%+)
Default

Thats great info TUBABOY... That really shows the point..

Now not to be a pain.. There is 2 things to consider.. Your comparing a 3200mah to a 4700mah pack(the C is different but im not truly concerned with that) You have 1500mah more in that pack that will hold your Average discharge voltage and punch higher longer... And i think it more important since you are running onroad to keep that AVG VOLTS higher. The other thing that i see is that you get progressively faster as the event went on.. This is probably typical of most of us, learning the track, possibly there was a resort that grouped u with similar drivers which would help with a cleaner faster run

It would be interesting to see a 20$ 5000mah pack go up against the that SMC... just for s h i t s and giggles.

customer service your bang on. Danny from SMC stands behind his stuff. He has more then helped me along over the years..

Anyway im not trying to bash on any brand, just see how close those knock off are to the REAL thing..

RE: ROAR. our club is not ROAR most if not all of us 2C charge our stuff. 2C rates are not at all a safety issue in my opinion...
__________________
"Without Rules its just Backyard Bashing!"
www.rcottawa.com
Joel Lagace is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Electric 1/8th Scale conversion kits. DJ1978 Electric Off-Road 19923 06-12-2017 05:16 AM
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks John Stranahan Electric On-Road 1776 03-01-2016 12:18 PM
3S Lipo in 1/8 Buggy? JLinney Electric Off-Road 30 02-15-2010 03:20 PM
Pro10 Class JimmyMac Electric On-Road 1085 08-07-2008 08:19 AM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 05:51 PM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net