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Old 03-27-2012, 10:46 AM   #16
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Rule of thumb has always been lighter=faster until you are so light that you cannot gain traction due to lack of vertical force(wether its weight or downforce)That is where the shell comes into play.
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Old 03-27-2012, 10:50 AM   #17
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Originally Posted by alcyon View Post
hm.. i thought a slightly heavier rear end would do some good? right now my car is 50.25% rear that translates to 21g heavier at the back, and it handles superbly without losing rear traction even in the tightest turns. These shorty packs are worth a try on my old school 414 type TC to cut weight.
Most of this discussion has been about Left/Right balance, which should always be equal for circuit racing. Front/Rear is down to car type, track conditions and personal preference. I run 50% rear in the dry and 53% rear in the wet for a bit of extra traction out of the corners.

Shorty lipos should be ideal in a 414; less weight and more room for your electrics. I'm designing a modern TC around them which is covered in a separate thread here:

http://www.rctech.net/forum/electric...ect-tc6-c.html
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Old 03-27-2012, 11:50 AM   #18
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Shorty LiPos can also better the handling by centering the weight. The car will more easily turn, which should be a big improvement indoors. Actual TCs are not benefitting from this yet, because their design is for normal Lipos and the motor is so far behind the center. With a little redesign nearly any of the professional TCs can be adapted to shorties including a forward moved motor.
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Old 03-27-2012, 08:02 PM   #19
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Shorty LiPos can also better the handling by centering the weight. The car will more easily turn, which should be a big improvement indoors. Actual TCs are not benefitting from this yet, because their design is for normal Lipos and the motor is so far behind the center. With a little redesign nearly any of the professional TCs can be adapted to shorties including a forward moved motor.
The ta06(car I am running) is designed to have a center mounted battery. I am also running the exotek conversion which makes the chassis even narrower. It's just this chassis is belt driven front and gear driven rear. It's heavy. Espically when you need to upgrade the tamiya plastic to aluminum parts for added stiffness.


I'm at 1390 with body and shorty lipo. I'm satisfied with that.
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Old 03-28-2012, 06:18 PM   #20
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Originally Posted by daleburr View Post
Most of this discussion has been about Left/Right balance, which should always be equal for circuit racing. Front/Rear is down to car type, track conditions and personal preference. I run 50% rear in the dry and 53% rear in the wet for a bit of extra traction out of the corners.

Shorty lipos should be ideal in a 414; less weight and more room for your electrics. I'm designing a modern TC around them which is covered in a separate thread here:

http://www.rctech.net/forum/electric...ect-tc6-c.html
i saw your build thread and i think its awesome. you and a few others have started the ball rolling in new direction when the manufacturers are still stuck with the 415 type design which seems not right to me. As for me, i already find my Kawada Alcyon II with saddle packs works really great traction and steering wise, and with the shorty packs i should be able to bring the weight down to legal minimum weight and also keep the front rear balance at 50-50. i am negotiating a deal on shorty packs to test them out.
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Old 03-28-2012, 10:04 PM   #21
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i saw your build thread and i think its awesome. you and a few others have started the ball rolling in new direction when the manufacturers are still stuck with the 415 type design which seems not right to me. As for me, i already find my Kawada Alcyon II with saddle packs works really great traction and steering wise, and with the shorty packs i should be able to bring the weight down to legal minimum weight and also keep the front rear balance at 50-50. i am negotiating a deal on shorty packs to test them out.
In sedan, I'm just not getting the power needed out of the shorty packs to compete. I'm going to try saddle packs next. I'll be trying them in my 414 and TA06.
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Old 03-28-2012, 10:59 PM   #22
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In sedan, I'm just not getting the power needed out of the shorty packs to compete. I'm going to try saddle packs next. I'll be trying them in my 414 and TA06.
are you running blinky or boosted. for the 414 i think saddle pack will work great becuase its a very light car.
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Old 03-29-2012, 03:05 AM   #23
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Yes, you will find full size road race cars with a side weight bias... but you make other good points. Maybe that's why I don't win more...
A TCS Mini may not qualify as a "race car", but when Lipos first became available they were very light and we lost the handling. Weights helped A LOT. Then the batteries got heavier again, and we could remove SOME of the weights. Minis also have cross-mounted batteries, so it's easy to slide them around and use tape to secure. Positioning for 50/50 was not the hot set up at Tamiya track.
I hope this thread stays popular. Many of you guys know so much, your input is valuable and anticipated!
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Old 03-29-2012, 07:34 AM   #24
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are you running blinky or boosted. for the 414 i think saddle pack will work great becuase its a very light car.
Blinky
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Old 03-29-2012, 09:23 AM   #25
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Why the fascination with weight cutting? My limited experience shows light cars don't handle very well road racing...

I'll take a 12th scale car over a sedan any day..
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Old 03-29-2012, 10:29 AM   #26
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Yes, you will find full size road race cars with a side weight bias... but you make other good points. Maybe that's why I don't win more...
A TCS Mini may not qualify as a "race car", but when Lipos first became available they were very light and we lost the handling. Weights helped A LOT. Then the batteries got heavier again, and we could remove SOME of the weights. Minis also have cross-mounted batteries, so it's easy to slide them around and use tape to secure. Positioning for 50/50 was not the hot set up at Tamiya track.
I hope this thread stays popular. Many of you guys know so much, your input is valuable and anticipated!
I have always found that a balanced car is much more predictable then a weight biased car. For me the predictability is much faster then weighting the car to handle some turns better than others. I tried a left side heavy car and the time I saved on some turns was wasted on the others. I actually got better lap times by balancing the chassis.

I agree with your points about the minis. A car can be too light. Overall weight is also a balance between too light and too heavy.
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Old 03-29-2012, 06:22 PM   #27
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Blinky
i am curious as to what spec shorty pack are you using. back in 2008 when i was just starting with BL, we only had standard BL esc that did not have any boost, just a standard AMTS timing. I used to have 2 sets of batteries. a Yeah Racing 3200mah 20C and a Yuntong 5000mah 20c.
I used to get 22mins of runtime on my 11.5T BL from the 3200mah battery. No problems of power down even after 15mins.
Now adays the shorty packs are 4000mah and has aC rating of 40 or higher, so i kind of dont understand why you are not getting the power. do you mean the punch? but i thought the C rating was supposed to take care of that.
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Old 03-31-2012, 12:04 PM   #28
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Originally Posted by alcyon View Post
i am curious as to what spec shorty pack are you using. back in 2008 when i was just starting with BL, we only had standard BL esc that did not have any boost, just a standard AMTS timing. I used to have 2 sets of batteries. a Yeah Racing 3200mah 20C and a Yuntong 5000mah 20c.
I used to get 22mins of runtime on my 11.5T BL from the 3200mah battery. No problems of power down even after 15mins.
Now adays the shorty packs are 4000mah and has aC rating of 40 or higher, so i kind of dont understand why you are not getting the power. do you mean the punch? but i thought the C rating was supposed to take care of that.
Im running 7.5R boosted. but im running a thunderpower 3800mah 65c. I think I should be fine.
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Old 03-31-2012, 08:26 PM   #29
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you know there is something we have not considered. yes the shorty packs are way lighter than standard packs, but as their capacity increases over time, so will the weight. remember in 2008 lipos were lower in capacity and C rating. a yeah racing 3200mah back in 2008 weighed at 202g. nowdays its not uncommon for a 6000mah stick pack to weigh 300 - 330g. my 5400 IP saddle packs weigh 280g. becuase of that my car weighs at 1480g. by using the shorty packs i can bring the weight down to the minimum limit of 1400g. howvere, once bateery capacity increases, so will the weight and we will be back to square one.
Right now there are a few shorty packs on the market. The fusion 4000mah weighs 200g. the IP 4400mah weighs 218g. the ORCA 4500mah weighs 222g. notice the higher the capacity, the higer the weight. so i guess there is no free lunch after all. No matter, i definitely want to try the fusion 4000mah just to see if it can save me on tyre wear due to the lighter weight.
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Old 03-31-2012, 08:53 PM   #30
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I picked up a thunder power 3800 mah 65c and it's just under 200 grams @ 198.8. (banana plugs)

It was $90.
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