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Old 09-14-2005, 09:23 PM
  #76  
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Originally Posted by Jack Rimer
So the question is- would you rather be faster for 6 minutes and slower for 2 minutes or faster for 2 minutes and slower for 6 minutes???? Is this a trick question? lol.
Agreed!!

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Old 09-14-2005, 09:26 PM
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Josh,

For TC stock, thats all you need, stock oval too. However If you get deep into discharge though you will have a speed disadvatage at the end of the race. That is 315 seconds at 30A discharge, most classes average discharge throughout the race is higher than 30A unless you go to 12th scale classes which run 8 minutes. You are also assuming you can get a big lead in the first few minutes, what happens if you don't get that lead?

The test was done 3 or 4 weeks ago with brand new cells.

I do like them for sedan and oval stock classes where you don't get that deep into discharge. I don't race those classes myself.

Chris
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Old 09-14-2005, 09:37 PM
  #78  
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Just to add a little perspective....

The actual percentage difference in voltage assuming a .1v difference is less than 2 %. We aren't talking about a huge amount here.

Chris
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Old 09-14-2005, 09:44 PM
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Great info Dusty, I asked you about the difference at Ripon last Saturday and I know others are facing the same decision as we enter carpet season.

Cheers!
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Old 09-14-2005, 09:54 PM
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Thanks Robert,

I think it will be a horses for courses thing, I really like that there is two good cell manufacturers out there, it can only be better for us racers.

For me, I feel GP's work better, no matter what information is out there it's still something we have to decide for ourselves.

Chris
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Old 09-14-2005, 10:18 PM
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Testing equipment is one thing but track testing is the ultimate test. Yes the discharge of curve of the IB cells maybe a slight bit lower near the very end but does this equate into lower lap times ?

When the battle between Panasonics and Sanyo was at it's best the panasonics didn't look that good on the TM4 but ran well on the track. Based on graphs and the TM4 Sanyo cells should of been much better. The fact is that both cells ran well.

If you run your 12th scale with an 8 turn with GP cells and can go the same speed with an IB pack and a 9 turn the effiencey you gain with the 9 turn will allow you to use less of the battery and finish faster.

Anyway based on your testing info it means that IBs definately have an edge for stock and 19 turn racing. Now we need to see what they do in 12th scale mod and Sedan mod. Josh Cyrul and Ralph BUrch have bothe confirmed that IB3800 are extremely good in Sedan mod and they feel it might allow them to run an 8 turn instead of a 7 turn and go as fast.
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Old 09-14-2005, 10:34 PM
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Just some questions... you said you did this test 3 or 4 weeks weeks ago with fresh cells. Are you sure these IB's are from the latest batch? Who matched these cells (both 38 and 37's) and how did the matching numbers compare between the the GP's and IB's... also I understand you didn't do these tests at the same time and relied on a previous test for the GP numbers... did you keep the two tests identical... ambient temperature etc?
Not bashing you just trying to understand your testing better
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Old 09-14-2005, 10:57 PM
  #83  
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Originally Posted by Kenneth Tan
Has anyone actually noted the number of charge/discharge cycles, in race conditions or bench tests, that a good IB3800 pack can go through before a major decrease in performance? Thanks.
the majority of us racers want durability. we can't afford to buy new packs every 1 to 2 months. if the 3700s are still more durable than the latest batch of IBs, then I'm willing to sacrifice a bit of runtime and voltage for longer lasting packs. the GP3300s were wonderful.
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Old 09-14-2005, 11:48 PM
  #84  
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The problem is that in Europe you cant use the IB3800 cells as they arent aproved by Efra yet (dont know if they ever will be). So for EFRA racing the comparison should be between IB3600 cells and GP3700 cells as theas are the ones alloved to race.....
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Old 09-14-2005, 11:53 PM
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Originally Posted by Ec1
The problem is that in Europe you cant use the IB3800 cells as they arent aproved by Efra yet (dont know if they ever will be). So for EFRA racing the comparison should be between IB3600 cells and GP3700 cells as theas are the ones alloved to race.....
As the 3800 is IFMAR approved as well as Roar approved there canīt be any reason it wonīt be EFRA legal, as long as Intellect send them in, in time, for approval. That could be earliest April 1, 2006.
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Old 09-15-2005, 04:49 AM
  #86  
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Originally Posted by ottoman
Just some questions... you said you did this test 3 or 4 weeks weeks ago with fresh cells. Are you sure these IB's are from the latest batch? Who matched these cells (both 38 and 37's) and how did the matching numbers compare between the the GP's and IB's... also I understand you didn't do these tests at the same time and relied on a previous test for the GP numbers... did you keep the two tests identical... ambient temperature etc?
Not bashing you just trying to understand your testing better

Ottoman= Chris and I spoke yesterday and he told me that he had gotten the cells from a very well know matcher and the matcher told him that they were the latest batch. I don't want to name drop, but that's why Chris didn't mention where he got the cells.

Chris has done an extensive test on the cells and at 30 amps with the same equipment will yield you those results above in the graphs. Chris also makes sure the ambient temp is the same along with other values that can change the results.

I know your not trying to bash but you have to understand, if your going to do head to head testing on things such as batteries then you need to keep the test between the two different cells identical. Chris would make SURE that the cells were done in identical settings.
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Old 09-15-2005, 05:46 AM
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Crimson, thank you for the info about the 2 packs it's good that you will take the time to inform us racers, nobody doing this not even the matchers so your information is top notch for us that BUY our cells we can make decision from the work you did, now on the 1/12 do you deadshort your pack? if so, with stock do you make the runtime.
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Old 09-15-2005, 06:26 AM
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One thing to think of during a race is you are on and off the throttle a bunch. The discahrger is a constant draw. If you were to use a discharge curve that would simulate a real race. The numbers would be more acurat. And I think really show that the IB is the better cell for voltage.
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Old 09-15-2005, 06:35 AM
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The fact that the voltage curves cross at about 360 seconds means nothing for stock 12th scale racing. We aren't averaging 30 amps in stock guys...If we want to pull 30 amps we're going to need cells closer to 500 seconds (480 plus last lap). Even if we could average that kind of current on the track the motors would heat up and drop off way more than the batteries would.

I was able to dump with GP3300's that had 430 seconds of runtime at The Gate when we ran Nats there and you know what? My car was a complete pile. Pushing, flipping, and a hot motor that fell off 6 minutes in. The problem wasn't the batteries, it was the car and the heat in the motor. Run that much current in 12th stock and you'll be slow.

At other tracks when the car was working I was using 350 to 380 seconds of runtime (figured from what was left in the pack). The 3800's may fall off more at the end but it's not going to be a big deal in stock.

In mod we have so much power that you can spin up the rear end at almost every track that I've been to. A little less voltage at the end will mean nothing as long as you don't dump. In mod, dumping is very dependant on set-up and driver. The battery is secondary for everyone except the top racers.

Vegas will tell the story on what cells will be better for each class...

Last edited by Unregistered; 09-15-2005 at 07:01 AM.
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Old 09-15-2005, 06:59 AM
  #90  
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Forget bench testing and numbers - GPs run better on track than IBs.
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