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Old 09-17-2009, 09:32 PM   #316
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The RX pack isn't going to back feed and give the motor more power.

I feel it's faster only because it will prevent ANY power from being taken away from the motor. If you run a booster there is a small amount of power being used for the receiver and servo, while minor it's a difference especially in mod where they're pushing it as it is.

If I had the choice I'd go rx pack simply to keep my servo and receiver at a higher voltage for optimal performance.
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Old 09-17-2009, 09:39 PM   #317
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hey randy,

I can't thanks you enough for all the help before and during the IIC. I wish I had a chance to thank you in person, but I was sooo beat saturday that i was just trying to get all my crap together to send back to texas. I am sure I will talk to you soon. but thanks again for all the help. only wish I could have done more for ya and tekin at the iic


yang
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Old 09-17-2009, 09:51 PM   #318
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Took my 1S 13.5 to the track to show Clegg how it was set up. Ended up racing. I can say that with a quality pack, I had no problems with a booster. My gearing and timing might be off, but I didn't have time to mess with it. My laps got faster as the traction came up in each heat and the main. Again, 3.7V taken out in parallel should have almost no noticeable affect on the ESC. It might load the battery a little current wise, but it isn't taking anything away from the motor. The mA the receiver and servo need are minute compared the amps the motor draws.
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Old 09-17-2009, 09:56 PM   #319
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Took my 1S 13.5 to the track to show Clegg how it was set up. Ended up racing. I can say that with a quality pack, I had no problems with a booster. My gearing and timing might be off, but I didn't have time to mess with it. My laps got faster as the traction came up in each heat and the main. Again, 3.7V taken out in parallel should have almost no noticeable affect on the ESC. It might load the battery a little current wise, but it isn't taking anything away from the motor. The mA the receiver and servo need are minute compared the amps the motor draws.

Yeh unfortunately I didnt get to play with your WGT car much, but it looked very smooth and easy to drive... my car was an absolute nut case tonight.
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Old 09-17-2009, 10:26 PM   #320
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With regards to the comments about a receiver pack or booster for mod. I dont know what the tekin is rated to but my understanding is that you have other escs rated to around 100-150A
I assume the RS Pro would easily match this so 300mA draw is pretty small compared to this.

I also note that the IIC setups of Mike Dumas and Donny Lia were running the current limiter at 84.

But im a pretty ordinary driver....
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Old 09-17-2009, 10:41 PM   #321
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They were running Mod motors, running in dual mode, using the RS Pro and were pulling huge amps. I'd like to know how many mAh were needed to recharge their packs. I think there may have been fear they didn't have enough juice to last the full race and still power the electronics.
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Old 09-17-2009, 11:10 PM   #322
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Its really quite simple, even if its called a booster, you can't make something out of nothing. You can fool the electronics into thinking the voltage is there to operate and even with the smallest amount of current draw you begin to tax the electronics to stay operating, and not efficiently. That doesn't matter if its with a mod or a 17.5 motor, the demand of the unit, although it sort of works, is not the best method. Mr Pike already stated that a rxr pack is the better method, like it or not, sometimes you can't fight the technology.

Had nothing to do with run time.
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Old 09-17-2009, 11:21 PM   #323
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Its really quite simple, even if its called a booster, you can't make something out of nothing. You can fool the electronics into thinking the voltage is there to operate and even with the smallest amount of current draw you begin to tax the electronics to stay operating, and not efficiently. That doesn't matter if its with a mod or a 17.5 motor, the demand of the unit, although it sort of works, is not the best method. Mr Pike already stated that a rxr pack is the better method, like it or not, sometimes you can't fight the technology.
Sorry, I let my electronics degree get the best of me sometimes. Randy didn't say better, he said preferred. I can see why, but again its not necessary for a 13.5 or 10.5 only running for 8 minutes. At one of my old jobs we used to use DC to DC step up converters. The key is it must provide a higher voltage at a lower current. Since the current draw is low on the battery to the booster its quite easy to double the output voltage at the lower current value as long as the voltage and starting current do not change. The problem occurs when the current drops below the the threshold to provide enough power to the booster. For us that's about 12 minutes. For a mod motor, they're cutting it close.
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Old 09-17-2009, 11:46 PM   #324
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I understand what you saying, but I think you'll find that with a 1s there will be more people going to the rxr pack versus the booster. Since we are concerned not only with keeping the "on" voltage to smarts of the sc, and taking into account trying to maintain a good speed on the steering servo, not having any kind of drop off at the rxr, so it has to re-search for dropped signal, and probably keeping a fan running on the motor to, I think that no matter, the booster won't do the best job.
Step up and step down convertors just aren't the same as raw available power such as what a rxr pack can supply.

At the IIC even the stock guys, the fast ones, used external rxr packs over boosters,

but if you have something working for you, go for it.
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Old 09-18-2009, 12:02 AM   #325
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I dont really know electronics, but from what i can see of the boosters they have caps on them which my understanding should theoretically maintain the voltage to the receiver and servo (assuming they are of sufficient capacity).

One of the guys i know, i think was toping up his receiver pack after each run or each second run (which i dont want to bother having to do). In fact im thinking about getting 4 lipos if they work so i can charge the night before and not have to worry about it on the day :P

I also saw in one of the british sites that one guy commented he ran a 4t and only used 2500mah at a rollout of 27mm. While another commented he ran a 5.5 and 36mm with a booster and used between 3000-3200mah. I was pretty astounded and asked it was 5 minute racing.

Both were running a tekin
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Old 09-18-2009, 07:43 AM   #326
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Hey guys,
What sort of rollout are people running on the RS with 1S Lipo and a 10.5 motor ?

I've got the speedo set to boost 20 and turbo max at the moment on a Nosram Storm motor.

Thanks
Chris
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Old 09-18-2009, 08:02 AM   #327
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Originally Posted by Johnny Wishbone View Post
I understand what you saying, but I think you'll find that with a 1s there will be more people going to the rxr pack versus the booster. Since we are concerned not only with keeping the "on" voltage to smarts of the sc, and taking into account trying to maintain a good speed on the steering servo, not having any kind of drop off at the rxr, so it has to re-search for dropped signal, and probably keeping a fan running on the motor to, I think that no matter, the booster won't do the best job.
Step up and step down convertors just aren't the same as raw available power such as what a rxr pack can supply.

At the IIC even the stock guys, the fast ones, used external rxr packs over boosters,

but if you have something working for you, go for it.
I'll admit I do it for the convenience. I don't need to worry about a battery that needs to be charged every 2 or 3 runs. I pit for myself and my son for 2 other classes. On any given race day I'm rotating 4 or 5 cars through charging, damage check, setup check and change and cleanup between rounds. My son doesn't appreciate it, yet... "I'm just a racer Dad!". In his defense, he's only 11. I can see where a pro/talented amateur racing one or two classes in the field the size of IIC or a ROAR Nat would want to go the RX pack route though. I'd wouldn't mind seeing an actual comparison from someone with proper equipment to see if there is an actual difference. The one posted earlier shows it in theory, but we need proof of concept now.
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Old 09-18-2009, 08:05 AM   #328
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Vegas setups for 1s:
Hey Randy
The gearing on the setups, is that FDR or rollout? I think its FDR, but not sure.
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Old 09-18-2009, 08:07 AM   #329
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Originally Posted by chris_dono View Post
Hey guys,
What sort of rollout are people running on the RS with 1S Lipo and a 10.5 motor ?

I've got the speedo set to boost 20 and turbo max at the moment on a Nosram Storm motor.

Thanks
Chris
Spoke too soon..... The 13.5 guys were running 3.04 something 2 pages back. My 13.5 is at 67mm rollout and is very quick.
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Old 09-18-2009, 08:23 AM   #330
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pan cars we always talk roll out. the difference is that some use metric and some use standard. the 3.04 is in inches
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