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Old 07-05-2014, 08:26 AM   #46
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I painted a LTC-r LW today.

87g with thick wing, head and tail lights only and minimal paint.
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Old 07-05-2014, 08:42 AM   #47
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I depends how many stickers and paint you cake on your body. If you paint them lightly and only use a couple stickers you can achieve 65 gram bodies.
Ie: just like you see Rheinard et all running in quali typically - single colour, minimal sponsors, paint so thin it's translucent.
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Old 07-05-2014, 12:08 PM   #48
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1380g - 1170g equals 210grams........ The $75 thunderpower 3300mah 65C weighs 208grams and will be perfect for your case.... Any heavier lipo packs will be detrimental to your car's performance...Try to lighten your car as much as possible to make room for heavier packs...
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My car weighs in at 1170g without a battery, would using a 300g battery still be wise (orca 6200mah 90c). I don't need the most competitive car, but I would still like to be able to compete
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Old 07-05-2014, 06:34 PM   #49
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I run a 4200 65c shorty in my tc and wouldn't change it unless I was forced. I likel the light weight and ability to move it around to help weight distribution. As far as weight you also have too see if your track has a minimum weight. Both tracks I race at have a minimum. One is 1380 grams the other is 1400
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Old 07-05-2014, 10:31 PM   #50
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I think I need to get a shorty and a standard size and start experimenting on the track and see whats better. I calculated the shorty LiPo+ titanium screws will get me to 1400g, which is quite respectable

Reason for a shorty over a full size lightweight pack is that I can move some of the electronics to the battery side

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Old 07-06-2014, 12:17 AM   #51
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I predict the full size will prevail in the end cause the drop off will be slight if any. The shorty may seem to be fast in the beginning but will drop off much more severe.
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Old 07-06-2014, 02:01 AM   #52
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I've never noticed any drop off over a 5 minute run with a shorty I could run 2 qualifiers easily if I wanted. I run just as much timing and run just as hard as everyone else and I just don't seem to use up all my battery over a 5 min race
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Old 07-06-2014, 06:39 AM   #53
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I've never noticed any drop off over a 5 minute run with a shorty I could run 2 qualifiers easily if I wanted. I run just as much timing and run just as hard as everyone else and I just don't seem to use up all my battery over a 5 min race
Well then don't ever get rid of that battery. First one I've heard of that doesn't drop off. Yes you could easily run a pack two times. However the 2nd time it wouldn't be as strong and have an extreme drop off after a few minutes.
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Old 07-06-2014, 08:10 AM   #54
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Voltage dropoff is negligable in 17.5t racing........ The top drivers use to race 5 minute mains with 7t brushed motors and 3300 nimh packs, so why shouldn't we race 17.5t with a 3300mah lipo ??? Simple economics.....
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I've never noticed any drop off over a 5 minute run with a shorty I could run 2 qualifiers easily if I wanted. I run just as much timing and run just as hard as everyone else and I just don't seem to use up all my battery over a 5 min race
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Old 07-06-2014, 08:58 AM   #55
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Voltage dropoff is negligable in 17.5t racing........ The top drivers use to race 5 minute mains with 7t brushed motors and 3300 nimh packs, so why shouldn't we race 17.5t with a 3300mah lipo ??? Simple economics.....
EVERYBODY who raced high level mod used 3300 packs with those 6 & 7 turn motors so they were on a level playing field. My guess is that the voltage/speed difference from start to finish was HUGE but accepted because every car dealt with the same drop-off.

I can see if you have a heavy tub-chassis car wanting to use a shorty or low capacity lipo, but any modern TC with a LW shell can usually make 1380g using a 7500 or 7600 lipo, even if its a minor voltage advantage its still there and it will help in a limited power class.
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Old 07-06-2014, 09:02 AM   #56
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Voltage dropoff is negligable in 17.5t racing........ The top drivers use to race 5 minute mains with 7t brushed motors and 3300 nimh packs, so why shouldn't we race 17.5t with a 3300mah lipo ??? Simple economics.....
I have no problem noticing voltage dropoff on a 13.5T, it manifests as less overall punch and lower top speed on the straights.

Edit: If I'm not mistaken, a mere 0.1 V drop equals roughly 300 rpms off the top end of an unloaded Speed Passion 13.5T brushless motor, so it's not just in my head either
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Old 07-06-2014, 10:40 AM   #57
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Voltage dropoff is negligable in 17.5t racing........ The top drivers use to race 5 minute mains with 7t brushed motors and 3300 nimh packs, so why shouldn't we race 17.5t with a 3300mah lipo ??? Simple economics.....
They have the motor to negate the voltage drop off. It's noticeable just not big deal. Same thing happens with like 4x4 short course. They have the motor you can only really see the drop off towards the end of the race. Or even after that. With 17.5 after the first minute or two there's difference in lap times.
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Old 07-06-2014, 12:42 PM   #58
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Originally Posted by d16dcoe45 View Post
EVERYBODY who raced high level mod used 3300 packs with those 6 & 7 turn motors so they were on a level playing field. My guess is that the voltage/speed difference from start to finish was HUGE but accepted because every car dealt with the same drop-off.

I can see if you have a heavy tub-chassis car wanting to use a shorty or low capacity lipo, but any modern TC with a LW shell can usually make 1380g using a 7500 or 7600 lipo, even if its a minor voltage advantage its still there and it will help in a limited power class.
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Old 07-06-2014, 02:38 PM   #59
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Maybe I'm not as in tune as some of you guys but I just don't notice any drop off. I run shorty for the finer weight placement. my tub car is fairly light so I use full size packs to make weight in vta not to combat drop off
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Old 07-06-2014, 11:38 PM   #60
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Specially when BERT's faster than you....lol........
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