Cain

iTrader: (294)

Welcome to electric.

For the Hyper 9E, you want to go with an motor in the 1800 - 2000Kv and range on 4S. For 3S, some people are using either the 2650Kv motor from castle, or even the 2200Kv motor.

the Tekin 1900Kv system is popular for the Hyper 9E since its Kv is lower, and you get more gearing range (15T pinion is about smallest you can fit with the Tekin or castle motors unmodified). The Castle system for being sensorless actually works well and can be found for reasonable prices if you look. Also, for the Tekin system, I would personally recommend you buy the Hotwire unit as well.

For batteries, I know those who really like the newer maxamps packs and also those who run SMC packs. I personally like PolyRC from my experiences and run the following:

Tekin 1900Kv Combo
PolyRC 6000mah 4S 25C pack (can be found at rclipos.com)

The 6000mah pack gives really great runtimes on 4S.

if you need hardcased lipos, there are a few options out there too and more on the way.

Main thing with the Hyper 9E is to keep in mind that the battery tray width is a tight 47mm max. The PolyRC pack I use fits snug.

Quad Racer 34

iTrader: (4)

so should i run a 5s lipo with either one of these setups rather than a 4s too keep it cooler and more efficient? because on this one http://www.amainhobbies.com/product_...r-Combo-2650kV it says up too a 6s lipo.. so what would be the best and most efficient lipo with this setup(2650kV)?... or with the Tekin setup 2200kV..?

EDIT: ok thanks you answered my questions since im going to be getting the Hyper 9e. thanks. and what kind of runtimes are you getting with the H9E with the 4s?

Quad Racer 34

iTrader: (4)

so people are actually running a 3s lipo with the 2200 kV? is there a advantage or disadvantage to that at all? more efficiency (sp)? and would that cause less run times? sorry im new to this and going to have a lot of questions about all this. lol

Cain

iTrader: (294)

using the 4S lipo I have on the hyper 9E, I can get over 20 minute runtimes, at least, that what I was seeing with the Neu 1512 2.5D/F motor. the main reason i went 6000mah was I needed guarenteed 15 minutes runtimes, the quickest I have ever dumped this battery pack was 18 minutes but that was in the winter and i did have a lot of wheel spin. I would say consistent 20 minutes is VERY driver and track specific. But, 1/8 electric looks to be going for 10 minute mains max which means even the sub 5000mah packs on 4S can make runtime.

I don't have the link right now, but there is a nice calculator out there that someone can post that will tell you want kind of speeds you can expect based on your inputs (voltage, motor, etc). In general you try to gear for 40mph initially, and work from there. the problem with high KV systems is that you can't find a small enough pinion for some cars to get into a reasonable racing speed range, and then also get hot too quickly.

the good motors in general are more heat resilent (truggy sized long can motors more so than buggy motors), and you can gear up (within reason) to get your speed you need. Its easier to go with the lower KV setup and gear up to get speed, than to try and detune a motor to be slower.

From what I can tell, the common motor Kvs to use in general are:

1800Kv - 2200Kv - 4S
1600Kv - 1700Kv - 5S
1300Kv - 1500Kv - 6S

Again, this is just an estimate.

Also, in general from what I recall, with the variety of cell configurations, as you go up in cell count, you don't need as much mah to have the same kind of runtime:

4S 5000mah ~ 5S 4000mah ~ 6S ~ 3333mah

based on this formula:

Watts = Voltage & Ah

So for 4S:

14.8V x 5Ah ( which is 5000mah) = 74W




More voltage systems are more efficient and will run cooler. However, keep in mind that if you plan to run in roar events, 4S hardcased or 2S hardcased packs in series are legal only.

Guys were using the 2200Kv on 3S from what I understand in Hyper 9E as it gave them some nice gearing range and it worked well. I personally like 4S for what I do.

BFDSausage

I've always been under the impression (and theory backs this up) that the higher voltage you can run the better. The lower the voltage, 11.1 in the case of 3s, the more amps you'd have to pull to get the same amount of wattage (in an over simplistec formula VxA=W.) More amps equals more heat and , once again in theory, a less effecient set-up. By running 4s or 5s you'd be able to run the same or even more wattage with less amps keeping your ESC and motor cooler (given that it is geared correctly) and that is a good thing. That being said I've been told that 4s is the minimum for anything 1/8th scale, that doesn't mean I'm right, it just means thats what I've been told and subsequently led to believe.

I hope my grammar is ok as I've been drinking since I got off duty this AM,
Steve

SpEEdyBL

iTrader: (1)

Just an FYI, the 2200 that most people are refering to is also a truggy sized motor, as it is longer and heavier than a buggy sized motor. So it geared up for the difference in kv, it would actually be closer to the 2650 in terms of power.

The 2650 and it is too much on almost any track. It's not a matter of driver skill. You just can't lay down that power before exceeding the physical limitations between the tires and the ground. Since switching to the Tekin 1900, I couldn't have been more satisfied. The power still exceeds that of the nitros, I get between 19 and 29 minutes of runtime from 4500 mah depending on the track and temps rarely exceed 130F on 4s. Sure 5s or 6s on a lower kv motor could get me a few degrees cooler, but it's not necessary and not worth the extra height of the battery. If a single pack had two stacks of cells that are more sqaure shaped, then I may have gone 6s and a 1400 kv buggy motor, but I certainly have no reason to change now.

Cain

iTrader: (294)

I think the reason people shy away from 3S was mainly that the packs at the time when it was tried would not take it. Way too easy to puff a pack of the ones that were tops then.

I personally would say that yes, ideally, go with a higher voltage setup, but can 3S work, sure.

Also, higher voltage setups do not have to be a brick if you keep in mind that you go with a lower mah pack as I described.

EVILGRAFX

iTrader: (37)

Keep your RC8 and get one of the conversion kits, Associated, RC Product Designs, RC Monster, or Tekno. Pick one that's best for you, they're all good.

The RC8 is just as competitive as the other cars, you already have one and you already know how it handles.

Quad Racer 34

iTrader: (4)

im keeping it as nitro and im going to upgrade the shocks to the BB threaded shocks for next season. i run sportsman buggy with it and then next year my local track is having a 1/8th scale electric buggy class. so thats what ill race the Hyper 9e in.

Quad Racer 34

iTrader: (4)

ok thanks for all the info speedy and Cain. i think ill go with the 1900kV. im racing tomorrow so ill check out all the brushless buggy setups to see what they are running.

jdeadman

iTrader: (41)

Also with Higher voltages come Lower Current draws, Better efficency Which in turn gives you lower temps on the batteries, motor and ESC and Longer run times.


V=IR is your friend

Bondonutz

iTrader: (48)

Visit http://www.rc-monster.com/ for more info if needed, It's a strictly electric forum and all the parts you'll need for your conversion are availible at the RCM store.

BTW, Hyper 9E is a awesome choice but since you already have a great buggy you can save $$$ and just convert it.

Welcome to the Dark Side !