SMC 40C+ C-Max 7.4V Hardcase Lipos
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12-22-2008, 06:58 AM
#93
Is the release date finalised yet? There's nothing wrong with my 28C SMCs but I'm still hanging out to pick up a couple of these. In 10.5, my car is always one of the quickest down the straight and it's gotta be down to the power because people are using the same motor and rollout, 40C should continue the trend 
Packs should be in around the 20th of January.
12-22-2008, 07:39 AM
#95
Is this the date your distributors should be getting them?
For Foam Touring 17.5 do you think would there be an advantage waiting for the 3200 40c vs the 4000 28c? All I care about is laptimes. I currently run Orion 3200 20c and those seem to drop off about half way through the race a bit. I've also had these and used them in off-road since before SMC got into LIPOs so I'm looking to upgrade.
For Foam Touring 17.5 do you think would there be an advantage waiting for the 3200 40c vs the 4000 28c? All I care about is laptimes. I currently run Orion 3200 20c and those seem to drop off about half way through the race a bit. I've also had these and used them in off-road since before SMC got into LIPOs so I'm looking to upgrade.
12-22-2008, 07:49 AM
#96
It will take us a few days to cycle and start shipping them out.
As far as the difference between the 3200/40C+ and the 4000/28C that will need to be tested. Typically the higher capacity of the 4000 might equal out the voltage curve but the punch/burst power of the 3200 may still be a bit better. In some track tests we did do the 5000/28C and the 4000/28C ran very similar lap times even though the 5000 had an advantage on the voltage curve. So numbers and graphs can be good info it doesn't always add up to much on the track.
As far as the difference between the 3200/40C+ and the 4000/28C that will need to be tested. Typically the higher capacity of the 4000 might equal out the voltage curve but the punch/burst power of the 3200 may still be a bit better. In some track tests we did do the 5000/28C and the 4000/28C ran very similar lap times even though the 5000 had an advantage on the voltage curve. So numbers and graphs can be good info it doesn't always add up to much on the track.
12-22-2008, 10:27 AM
#97
Danny I was helping jlfx with our little home brew test. It all began with me talking about getting a new pack after the first of the year. blah blah blah. So then we got on the whole c rating thing and how this was measured (virgin cell). Then it got on the point that these c ratings have such an high amp flow, but does it really matter with the tech that we currently have (gauge of wire, solder, esc, motor). I may be way off but it would seem to me that if this true c rating were to flow into the esc it would smoke the speedo no matter what brand it was. Ok back on point so we got to the point that yea these packs (any brand lipo) say that they put out certain numbers but what do they really flow after the pack is put together (not knocking how the manufactures rate, but the rating is not practical for the end product to truely gauge energy flow in the application being used for per variables above). This little test last night was just round one while we waited on the wife and gf to get back after we had been racing all day. We also know that we have a range of packs at different points in their lifespans. Also we think that the harness made to hook up the TP pack had a bad deans connector. The first test was kinda a hey lets see what we got here, but I plan to try this some more with tighter controls. Any suggestions on how to conduct the test?
12-22-2008, 12:09 PM
#99
Danny I was helping jlfx with our little home brew test. It all began with me talking about getting a new pack after the first of the year. blah blah blah. So then we got on the whole c rating thing and how this was measured (virgin cell). Then it got on the point that these c ratings have such an high amp flow, but does it really matter with the tech that we currently have (gauge of wire, solder, esc, motor). I may be way off but it would seem to me that if this true c rating were to flow into the esc it would smoke the speedo no matter what brand it was. Ok back on point so we got to the point that yea these packs (any brand lipo) say that they put out certain numbers but what do they really flow after the pack is put together (not knocking how the manufactures rate, but the rating is not practical for the end product to truely gauge energy flow in the application being used for per variables above). This little test last night was just round one while we waited on the wife and gf to get back after we had been racing all day. We also know that we have a range of packs at different points in their lifespans. Also we think that the harness made to hook up the TP pack had a bad deans connector. The first test was kinda a hey lets see what we got here, but I plan to try this some more with tighter controls. Any suggestions on how to conduct the test?
I know many doubt about C rate but it does help some. As there is more to a packs performance than just the ability of that pack to give voltage at a constant load.
Feel free to email me at [email protected] and I can hel you with good testing setups to get accurate results.
12-22-2008, 01:33 PM
#100
We don't the c rating, but are just curious about the energy flow of a completed pack. I am sure that the cells have the c rating that they claim (virgin) from all reputable manufactures, but what happens after all the soldering and such are done, and at what point does the gauge and quality of the wires, esc, and motor past the pack begin to limit the flow of the pack. c rating seems to be kinda like car hp a company says 400hp but after it goes through the drive train you end up with with 380 to the wheels. If you keep upping hp and not upgrading the drive train there will be a point where the hp will break it. I will get an email out to you for some guidance on the matter of a good solid test. thanks
12-22-2008, 03:17 PM
#102
Tech Initiate
dear SMC
in your testing and experience with Lipos, is it true or false that increase in C rating, translates to decreased cycle life?
Why have 40C packs if they'll last maybe 20 cycles before they drop off and perform like 20C packs, paying almost $130 for those packs?
I'm concerned about that would like you to please clarify this, thanks
in your testing and experience with Lipos, is it true or false that increase in C rating, translates to decreased cycle life?
Why have 40C packs if they'll last maybe 20 cycles before they drop off and perform like 20C packs, paying almost $130 for those packs?
I'm concerned about that would like you to please clarify this, thanks
12-22-2008, 04:09 PM
#103
Not sure where that comes from but what makes for good cycle life is not the C rate it's quality of the materials used and the knowledge in making the cells/packs. With our packs the higher C rate will make for a better cycle life as the same high quality materials and knowledge is used.
12-22-2008, 09:48 PM
#104
Not sure where that comes from but what makes for good cycle life is not the C rate it's quality of the materials used and the knowledge in making the cells/packs. With our packs the higher C rate will make for a better cycle life as the same high quality materials and knowledge is used.
12-23-2008, 08:27 AM
#105
even if they did drop off, they sell them b/c people out there will buy them to get the edge on the next guy if only for a few wks. they sell all kinds of amp ratings nowadays and we all have a rating in mind for the car we want to buy a battery for..., so they can still sell u on that, just hope it fits. they cant sell u on voltage anymore as in the past and i dont see folks pasting IR info on their packs. they need somethin to 'sell' u on, and thats C. so how fast do you wanna go, how much you wanna spend, and how bad do you need to make your toy car faster?
personally, if it doesnt fit my car, i dont care what it is, not hackin the car to make it fit. too bad SMC doesnt make somethin that fits a f103, or else i'd buy it. as it stand now i'll prolly have to pay an extra 40bux for the 'O' sticker :/
at least the 24c 4100 fits nice in a TT01 (w/lead slab underneath for balance--sits it up from the chassis gussets that used to slide under the 6 individual cells) and beautifully in my CR for mod. cuz thats all that thing needs.
SMC, make somethin that is tamiya/stick friendly please
R
personally, if it doesnt fit my car, i dont care what it is, not hackin the car to make it fit. too bad SMC doesnt make somethin that fits a f103, or else i'd buy it. as it stand now i'll prolly have to pay an extra 40bux for the 'O' sticker :/
at least the 24c 4100 fits nice in a TT01 (w/lead slab underneath for balance--sits it up from the chassis gussets that used to slide under the 6 individual cells) and beautifully in my CR for mod. cuz thats all that thing needs.
SMC, make somethin that is tamiya/stick friendly please
R