17.5 tips and speed secrets
#151
Tech Champion

Joined: Oct 2007
Posts: 7,342
The firmware version determines if the Hyperion shows pack resistance or individual cells. Not positive, but if I remember correctly V5 or later is needed for individual cell readings. Cell readings are cool and all but since the full pack is what is actually raced I never bothered to update.
Consistency in all testing conditions, especially pack temperature, but also how long since last use, charge state, rate, etc, are always important for best results.
#153
Joined: Jan 2003
Posts: 8,616
From: New Jersey
30 amp discharge, 1 minute break, 20 amp charge.
#155
If you are going from mod (say an 8.5) to stock, then sometimes people will switch to lighter springs and oil because the momentum is less and there are sometimes less forces at play when there is weight transfer.
Note that this is sometimes.
With the mod motor, you will accelerate faster and consequentially often brake faster where the layout of the track permits you to - but not always. That is in some parts of the track the differences in speed you will be running will be smaller than in others.
It would seem from a physics standpoint that if you are accelerating less and braking less quickly then as the weight transfer is less severe, a lighter spring may give you a similar feel.
Try say, one step lighter all around, but also try the same springs when going from mod to stock.
I tend to tune for more weight transfer from rear to front in my stock car than my mod. I think this is because as I'm going slower there is less to shift the balance to my front wheels to give me steering when I want it. Hence I go proportionally with a little heavier spring in the rear to assist in that rear to front weight transfer.
Anyway, just my somewhat noobish attempt to give you some thoughts to try. Hopefully better drivers will jump in on this discussion as well.
#157
Joined: Jan 2003
Posts: 8,616
From: New Jersey
I know some people who own two of the same cars and have almost completely different setups for stock and mod. Others who change very little so obviously there is driving style and preference.
If you are going from mod (say an 8.5) to stock, then sometimes people will switch to lighter springs and oil because the momentum is less and there are sometimes less forces at play when there is weight transfer.
Note that this is sometimes.
With the mod motor, you will accelerate faster and consequentially often brake faster where the layout of the track permits you to - but not always. That is in some parts of the track the differences in speed you will be running will be smaller than in others.
It would seem from a physics standpoint that if you are accelerating less and braking less quickly then as the weight transfer is less severe, a lighter spring may give you a similar feel.
Try say, one step lighter all around, but also try the same springs when going from mod to stock.
I tend to tune for more weight transfer from rear to front in my stock car than my mod. I think this is because as I'm going slower there is less to shift the balance to my front wheels to give me steering when I want it. Hence I go proportionally with a little heavier spring in the rear to assist in that rear to front weight transfer.
Anyway, just my somewhat noobish attempt to give you some thoughts to try. Hopefully better drivers will jump in on this discussion as well.
If you are going from mod (say an 8.5) to stock, then sometimes people will switch to lighter springs and oil because the momentum is less and there are sometimes less forces at play when there is weight transfer.
Note that this is sometimes.
With the mod motor, you will accelerate faster and consequentially often brake faster where the layout of the track permits you to - but not always. That is in some parts of the track the differences in speed you will be running will be smaller than in others.
It would seem from a physics standpoint that if you are accelerating less and braking less quickly then as the weight transfer is less severe, a lighter spring may give you a similar feel.
Try say, one step lighter all around, but also try the same springs when going from mod to stock.
I tend to tune for more weight transfer from rear to front in my stock car than my mod. I think this is because as I'm going slower there is less to shift the balance to my front wheels to give me steering when I want it. Hence I go proportionally with a little heavier spring in the rear to assist in that rear to front weight transfer.
Anyway, just my somewhat noobish attempt to give you some thoughts to try. Hopefully better drivers will jump in on this discussion as well.
#158
Tech Addict
iTrader: (47)
Joined: Dec 2012
Posts: 629
Here's what your up against in the stock classes. This guy has some very informative vids and testing equipment.
https://www.youtube.com/watch?v=dZPVyA-xoGo
https://www.youtube.com/watch?v=dZPVyA-xoGo
#159
Tech Addict
iTrader: (10)
Joined: Jun 2009
Posts: 678
If you can build a light weight car, and comes in under weight, why not just settle for saddle packs or bricks, instead of shorty?
The saddle will produce a higher average voltage, however I'm not sure if the extra 75 grams could possibly put it at a disadvantage! Although maybe it won't be at a disadvantage, as I have heard the ideal weight for 17.5 2wd is around 1570grams. However with shorty, you can adjust weight bias, but seriously how often do you even need to change lipo position? I'd rather adjust weight bias with lead weights!
The saddle will produce a higher average voltage, however I'm not sure if the extra 75 grams could possibly put it at a disadvantage! Although maybe it won't be at a disadvantage, as I have heard the ideal weight for 17.5 2wd is around 1570grams. However with shorty, you can adjust weight bias, but seriously how often do you even need to change lipo position? I'd rather adjust weight bias with lead weights!
#160
Joined: Jan 2011
Posts: 4,121
If you can build a light weight car, and comes in under weight, why not just settle for saddle packs or bricks, instead of shorty?
The saddle will produce a higher average voltage, however I'm not sure if the extra 75 grams could possibly put it at a disadvantage! Although maybe it won't be at a disadvantage, as I have heard the ideal weight for 17.5 2wd is around 1570grams. However with shorty, you can adjust weight bias, but seriously how often do you even need to change lipo position? I'd rather adjust weight bias with lead weights!
The saddle will produce a higher average voltage, however I'm not sure if the extra 75 grams could possibly put it at a disadvantage! Although maybe it won't be at a disadvantage, as I have heard the ideal weight for 17.5 2wd is around 1570grams. However with shorty, you can adjust weight bias, but seriously how often do you even need to change lipo position? I'd rather adjust weight bias with lead weights!
#161
If you can build a light weight car, and comes in under weight, why not just settle for saddle packs or bricks, instead of shorty?
The saddle will produce a higher average voltage, however I'm not sure if the extra 75 grams could possibly put it at a disadvantage! Although maybe it won't be at a disadvantage, as I have heard the ideal weight for 17.5 2wd is around 1570grams. However with shorty, you can adjust weight bias, but seriously how often do you even need to change lipo position? I'd rather adjust weight bias with lead weights!
The saddle will produce a higher average voltage, however I'm not sure if the extra 75 grams could possibly put it at a disadvantage! Although maybe it won't be at a disadvantage, as I have heard the ideal weight for 17.5 2wd is around 1570grams. However with shorty, you can adjust weight bias, but seriously how often do you even need to change lipo position? I'd rather adjust weight bias with lead weights!
You're only thinking about the weights of the batteries themselves. A shorty allows you not only to move the battery around but put that weight savings over a saddle anywhere you want (C/D block, bulkhead, aluminum hubs, etc).
#162
Joined: Jan 2011
Posts: 4,121
Higher average voltage? Not sure about that. Maybe if we ran 10-12 minute mains. For most of us that run 6-8 minutes, I'd be surprised to see much if any difference in average voltage.
You're only thinking about the weights of the batteries themselves. A shorty allows you not only to move the battery around but put that weight savings over a saddle anywhere you want (C/D block, bulkhead, aluminum hubs, etc).
You're only thinking about the weights of the batteries themselves. A shorty allows you not only to move the battery around but put that weight savings over a saddle anywhere you want (C/D block, bulkhead, aluminum hubs, etc).
#165
Joined: Jan 2011
Posts: 4,121



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