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Old 08-20-2014, 08:01 AM   #2416
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Originally Posted by dodgeguy View Post
He already indicates his droop settings.

It is not a droop issue it is the actual part. The shock ends are soft and the threads become compressed causing the pull out.
Oops, sorry. 110mm in the rear is a ton, I don't even know how you get that much, but that may be part of the issue.
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Old 08-20-2014, 09:22 AM   #2417
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Oops, sorry. 110mm in the rear is a ton, I don't even know how you get that much, but that may be part of the issue.
110 is actually not alot and less then the stock setup by 2.5mm and 3.5mm-4mm less then most setups!
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Old 08-20-2014, 09:47 PM   #2418
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Thanks for the feedback on my problem. I will attempt to screw the shock ends further onto the shock shaft. I am measuring from center of top standoff screw to center of bottom screw using digital calipers. The fact that the shock ends may not be screwed on all the way could cause me to get longer lengths than others.
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Old 08-21-2014, 06:03 AM   #2419
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Thanks for the feedback!


Quote:
Originally Posted by UN4RACING View Post
Here's a copy and paste that may help.? For starters, the C in C Rating stands for capacity. The C rating is the maximum safe continuous discharge rate of a pack. If you see 10C on your battery, it means it can be discharged at 10 times that pack's capacity. Capacity refers to the milliamp-hour rating of the battery, which will be listed as a number followed by mAh (2000mAh).

Here's the easy way to find your battery's discharge rate just multiply the number from the C rating by the pack's capacity. Keep in mind that 1000 milliamps equals one amp. Here's an example, using an 11.1V 2000mAh 10C

11.1 volt 2000mAh -10C
2000 milliamps = 2 amps
2 Amps x 10 = 20 amps continuous discharge

This means that you can safely draw up to 20 amps continuously from that 11.1V 2000mAh 10C without doing damage to your battery.

My self, I run 6700MAH at 100C
6700 = 6.7 amps X 100C = 670 amps continuously. Keep in mind this is over kill. I doubt I am even capable of pushing that many amps through my Gen2 and 1900. At best I would be lucky to pull 180 amps out of a pack at full throttle. In short I am not stressing my pack at all.
I am skeptical of C ratings personally. My guess is I am able to pull around 150 amps?

Now lets say I am able to pull 180 amps from my pack with my esc motor combo?
A 5000MAH 30C would not be safe to run with out stressing the pack if I am able to pull 180 amps.

5000 = 5 amps X 30C = 150 amps.

In short a 30c pack would not last very long. Yet at 150 amps it would be the minimum I could run with out stressing the battery.

To sum it up you need to know how much draw your ESC motor combo can pull from the pack before you can find the minimum C rating or weight of pack you are looking to dial in for.
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Old 08-21-2014, 06:07 AM   #2420
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Originally Posted by ta_man View Post
This is the kind of post that, while the information may be literally true, the content is not helpful in answering the question. It actually confuses people who are starting out and may take the amp ratings literally.

The reason it is not helpful is the disconnect between continuous C ratings and the actual current draw of a car in racing conditions. Yes, the ESC may be rated at 120 amps continuous, but you never see 120 amps continuous in a race. Yes the motor may be rated for 100 amps continuous (with adequate cooling, but you never see 100 amps continuous in a RC car.

Point of fact: if a 1/8th buggy was drawing 100 amp continuous, you could only race 3 minutes on a 5000 mAHr pack. Yet many people get 10-15 minutes on a 5000 mAH pack and still have something left in the battery. I know from experience (in recharging a pack after a timed run) that my first E8 with a Neu 1512 motor drew an average of 18 amps over a 10 minute run. So even though that motor was rated at many thousands of watts, it was drawing less than 300 watts on average.

The continuous C rating and the motor ESC amp ratings are essentially irrelevant when looking at how many amps your motor/esc/car can draw. For two years I ran my E-8 on a Thunder Power 4300 mAHr 25C pack. Any high quality 40C-50C rated pack of reasonable capacity (4000-6000) should be sufficient for the current setups in E-8s.
Thanks for fine tuning that other post. It definitely shed alittle clarification. You mention high quality batteries. Since I'm new there are so many choices. Track power, thunder, gen ace, protek, smc. Out of these I'm looking at gen ace and smc since it would be easy on pocket after my initial build. Are these a good starting point as others have pointed out? Not stepping on others recommendations just looking for additional feedback as I research.
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Old 08-21-2014, 08:17 AM   #2421
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After somewhat understanding the importance of the C rating I see it would be important to know the esc/motor amp rating. How would I find the amp rating of the esc and motor? Is the amperage of the two static or can it be adjust with a programmer like the Hotwire 2 for tekin?
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Old 08-21-2014, 08:32 AM   #2422
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The couple set ups I've looked at don't mention shock oil weight. Are people using the provided 35 and 37.5 weight when building their shocks?
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Old 08-21-2014, 09:11 AM   #2423
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I like 37.5F 35R with the 8 hole pistons.
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Old 08-21-2014, 10:57 AM   #2424
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Originally Posted by SRW141 View Post
I like 37.5F 35R with the 8 hole pistons.
Are you using what is included in the kit?
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Old 08-21-2014, 11:18 AM   #2425
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Originally Posted by dpcardoza View Post
Are you using what is included in the kit?
I can't speak for everyone.. but I know most do not build with the kit oil. Build the car with regular tlr oil.
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Old 08-21-2014, 07:24 PM   #2426
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Quote:
Originally Posted by InARush View Post
After somewhat understanding the importance of the C rating I see it would be important to know the esc/motor amp rating. How would I find the amp rating of the esc and motor? Is the amperage of the two static or can it be adjust with a programmer like the Hotwire 2 for tekin?
The amp ratings on ESCs and Motors are the maximum continuous current they can tolerate for some set period of time without being damaged by the heat buildup. Within limits (very high limits) the shorter that "set period" is, the higher the amp rating will be for the same electronics configuration. (There may also be a burst racing for the ESC which is even less relevant.) That info is generally irrelevant for use in an off-road RC car when trying to decide on a battery. For example that Neu motor I mentioned was rated at a 1000 watts continuous, 2000 watts peak. It averaged 300 watts on the track, one third of its heat dissipation rating.

If you were flying an airplane or helicopter in competition where you were continuously at full or near to full throttle and maximum load, those numbers would be important in choosing a battery rating. But not for an RC car.

In a car, maximum current is used when accelerating from a stop, and so very rarely. In an airplane, the propeller has no load on it when starting up, so it is not until it reaches higher RPM that the load builds. RC Cars on off-road tracks don't go fast enough that the load from air drag exceeds the load from initial acceleration.

Some ESCs have current limiters that will reduce max current draw on acceleration.

IMHO, SMC batteries are way better than Gens Ace.
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Old 08-21-2014, 08:15 PM   #2427
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Originally Posted by symmetricon View Post
Oops, sorry. 110mm in the rear is a ton, I don't even know how you get that much, but that may be part of the issue.
Um you need to check all the pro driver setups for buggy. All are around or at 114mm from shock mounting center to center.
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Old 08-21-2014, 08:30 PM   #2428
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for whats it worth...I have used SMC batteries for about a year now and haven't had any issues. I use them in my 1/10 2wd...new 1/10 4wd...(never a problem with any battery) 1/8 scale is really the test IMO..i run 2-3c charging on all my batteries (there is more to it..gen 1 rx8 ..1900.. geared right.. etc) and they always end up at 4.2 ...even with the 4 cell and crazy loads of 1/8 scale..IMO if they don't puff and get crazy on 1/8 scale...cost what they do.. then i'm sold for all my cars..
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Old 08-21-2014, 08:50 PM   #2429
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Originally Posted by RevolutionM View Post
110 is actually not alot and less then the stock setup by 2.5mm and 3.5mm-4mm less then most setups!
Yeah, sorry again, I'm off my game right now lol. Most run between 113-116 lol or something around there.
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Old 08-21-2014, 11:18 PM   #2430
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I would like to share some pics of my 2nd hand 8ight-E 3.0 I rebuild. The new body I painted is according my color scheme:









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