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Old 08-25-2006, 10:45 PM   #1
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Default Do we REALLY need matched packs nowadays????

Im thinking that with the high voltage and runtimes with the new 3800's and 4200's do we really need to match them for them to be great?! I'm talking specifically in offroad uses. I mean after a 6 min mod race these things are only halfway dumped and still have plenty left! Wasn't the original purpose of matching batteries to make sure you had the same power before the pack dumped?? Now that this is really no longer a concern, what's the point??? There is now a better shot of your motors fading from heat than your batteries dumping before the end of a race.

Even when you do buy matched packs they slowly lose their match after every charge and discharge... With the new technology these batteries are running in the upper parts of their discharge curves for the whole race...

I think that as the batteries get stronger, the need for matching them gets weaker...
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Old 08-25-2006, 10:56 PM   #2
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nutfluff makes a good point. In offroad, I can't imagine any but the absolute top drivers being able to make use of the differences between high end match packed and lower grade.

Matched packs are still good to have, to keep cells in a pack similar. If you had packs with a few strong and a few run of the mill cells, you could damage the lower level cells, as they would/could be below .9v/cell during post race discharging (unless you discharge each cell). And taking a pack that's 1/2 way chaged down on a tray takes forever.
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Old 08-26-2006, 04:53 AM   #3
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I'm not running matched packs any more (IB4200s) and I have no isues with pace or runtime. The packs are still holding up after many cycles.

I'm sure some of the less scrupulous matchers either cook the cells to get big numbers or fake the labels anyway.

Top, top drivers with trusted suppliers probably benefit from matched still, the majority of us have no need now.
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Old 08-26-2006, 10:41 AM   #4
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I'm merely a club level racer, and I can still see the benifits. I have two 3800 packs, one built from a bulk pack of Epic cells that I split with another racer, and the other is a nice matched pack from B&T. The B&T pack has alot more punch, and I save it for the mains. The other pack is great, and often has higher capaicty(weird) but isn't as fast. When competing with other guys on the same level, the matched pack does help me. However, if you personally can't tell, then you shouldn't bother with the extra expense...
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Old 08-26-2006, 10:45 AM   #5
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for mod, I wouldnt worry about the matched packs. For stock YES...
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Old 08-26-2006, 12:01 PM   #6
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Matched batteries are like tuned motors. Matching a pack with similar runtime, voltage, and IR makes the overall pack better. You can have a really bad cell in an unmatched pack and not know it. Matching as I see it these days is just a way to weed out the bad cells. Just like motor guys dyno motors to know which ones are "top" performers and those that just do not "make the cut" a battery matcher will find underperforming cells that will hurt the performance of an entire pack. Now with todays cells the cases are much closer in the best cells vs the worst cells so the best vs the worst is not as big a gap and like you mentioned we are only using a small part of the capacity of these cells to begin with but the matchers ability to weed out the few bad cells helps make your pack even better. The zapping process do help with performance of the cell as well. Is it necessary to run matched batteries, no. Will matched battereies preform better, I believe most of the time. Again can you buy an untuned motor and have it be fast. Yes. Are the odds of getting a good motor that has been tuned and shows good on the dyno. I think so. The numbers on the batteries and motors are not gurentees they will be great performers on the track but your odds are a lot better with these then batteries and motors that have not been looked at by matchers and tuners.
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Old 08-26-2006, 12:41 PM   #7
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I do agree with what you say for stock...but in off road mod...you really just need the runtime which even the "bad" cells have. In the last worlds in Italy, most were just running 5 cells (traction/power problems) and having no issues. That shows me that even if you have a "bad" cell, you're not gonna be far off. We all can agree that voltage isn't as important in offroad as it is in onroad...I've heard that Kinwald didn't even run the highest voltage packs that wered available to him.

For the average racer, and especially those just starting out, too much "power" isn't the best thing. Granted us Sportsman at SoCal are very competitive but I know people who hang at the top with not the best batteries/motors because they can drive.

The reason I bring up the discussion is because I've noticed that after having some matched packs for awhile, they show they are not as matched as they were when new. When put on the Novak tray they all come down to .8 at different times yet the packs are very competitive. Even though I was running matched packs in the beggining, it appears I am no longer and not noticing a big difference. This is in stock.

I also agree that with matchers and tuners you do weed out potentially bad product...in this case do people then really need to be paying extra for that extra thousandth volt with the new batt technology. Nope.

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Old 08-26-2006, 01:20 PM   #8
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As Casper said above matching packs helps weed out the back cells. Buying matched packs is always a good idea. Now weither to buy higher voltage cells is a matter off what you race. If it is mod then the extra voltage is not really a big deal. In the 19T and Stock racing classes it is good idea to have a higher voltage pack in these classes because of having a fixed motor. The difference in performance is very noticeable. The nice thing is the lithum batteries are going to make matching a thing of the past. I can hear the battery matchers crying already. HURRY UP ROAR AND APPROVE LITHUM BATTERIES FOR STOCK AND 19T RACING!!!!!!!!!!!!!!!!
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Old 08-26-2006, 02:49 PM   #9
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I have practiced with a Lipo and stock and agree that it's a whole other world. But the difference in voltage and resistance is HUGE. But paying for extra hundreths I think is ridiculous and the difference is in people's heads.

Yes, overall matched provides you a "better" pack but doesn't make that big a difference over a 5 or 6 minute race if you need to be marshalled and the person with the "lesser" pack doesn't which is why I believe the average offroad racer doesn't need matched packs with the newer batteries.

Although batteries aren't the only part of the equation...if you have a great matched pack and a stinker of a motor it's all for nothing...and that's a different topic.

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Old 08-26-2006, 03:12 PM   #10
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I agree. Match packs are not "needed" until you get to the upper end of the racing world. For everyone else the low end stick matched packs or even stick packs with good cells in them will be plenty.
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Old 08-26-2006, 04:16 PM   #11
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In addition to the mod discussion, brushless motors help out 'average' packs even more, IMO. There is very little difference in power that I can see between my nicer matched 3800's and my unmatched, very old, 3300s. Seriously. Not much difference, but still there. A new, unmatched 3300 pack is no different to a new, matched 3800 pack when I'm driving. For me these days its either the pack is old, or new.
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Old 08-26-2006, 04:30 PM   #12
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hey sport10:i have heard that lipo batteries may be the wave of the future in r/c racing,but only if they get a little bit safer.just something i read else were.
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Old 08-27-2006, 04:33 AM   #13
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Quote:
Originally Posted by Laterilus
There is very little difference in power that I can see between my nicer matched 3800's and my unmatched, very old, 3300s. Seriously.
I find that with my old unmatched 3600's I can sometimes control my mod B4. With newer, well matched 3800's I can't control it. Too much punch.

I think it comes down to punch...
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Old 08-27-2006, 10:32 PM   #14
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First off all batteries are dangerous when mishandled. One nice thing about Lipo is that they are flammable but do not exploded like Nicd or NiMh cells will. The plastic case that Orion and Peak have on their Lipos is a very nice idea and adds an extra measure of protection from crash damage. I really only have seen lipos have problems when the user does not know how to properly charge and when to stop discharging them. The technology is already available to make these cells almost foolproof. Their are some companies that include circuits in their batteries that control the charging and discharging of their batteries.
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Old 08-27-2006, 11:43 PM   #15
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The Titanic was also supposed to be unsinkable.
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