Racing battery choices
 

So I am trying to decide what size lipo to get for racing, in particular, those 30 min mains. I have come to three choices based on what runtime I was getting with my old Hyperion G3 vx, 25 mins for a 6s 4200mah 35C pack.

1. Thunder Power RC G6 Pro Power 65C 2250mAh 6-Cell

2. Thunder Power RC G6 Pro Performance 45C 2700mAh 6-Cell 419 grams

3. Thunder Power RC G6 Pro Performance 45C 3300mAh 6-Cell 515 grams


The small 2250mah would need 3 sets of packs for 10 mins running time each, which any lap time savings might be negated by the battery swapping TWICE. I am not sure on the 2700mah, whether it would last 15 mins running or not, it would be super close, and maybe too risky? The 3rd option seems like a solid one with almost 20 mins running time each, so only one battery swap during a race.

Anyone with some veteran racing experience is happily welcome to put their two cents in on what you think of each. BTW, I run pretty smoothly, fairly constant throttle over the whole lap, besides the straights.

thanks

Are you overly concerned with weight for the reason of possibly choosing the smaller packs?

IMO, #3 would be a clear choice for one battery swap during the race. No need to put more times than you need to unless the rules state it. And I would hate for you to get 14 minutes of runtime on each pack of #2 and not finish the race.

What vehicle are you racing that gets 20 minutes of runtime on a 6s 3300mah pack? Hyperion packs get my vote - not just because I sell them, but because they are great packs and a great value. I use the 4200mah 5s packs in my buggy and truggy and couldn't get 25 minutes in a race situation even in my light 808 buggy.

Yeah, I am just wondering if the light weight pack is going to give me any overall benefit over the larger packs, but counting the 2nd battery swap into the total time, maybe not a gain there. But, I also have to pit twice regardless of whether I need to, to make it fair for the nitro guys... :neutral: But they say for the 2nd pitting, I only need to pit for literally 2 seconds and then off again.

Mike, I am racing in my converted Revo running my good old 1512/3D 1700Kv. and RX8, and at the track I was getting up to 25 mins on a 6s 4200 G3 pack, two 3s packs in series on each side of truck for cg and balance. So, going on that, the 3300 45C pack should be getting around 18-19 mins. I would only put back 2700-2800mah after 15mins running.

I am going for the Thunderpower packs this time around because they have a 2 year warranty, plus 50% off replacement for damaged packs. RCtoys or better known as draganfly are from my hometown here, so I don't have to pay for shipping cost, so they end up costing the same as Hyperion packs in the end. Hyperion would have been my 1st choice otherwise.

When I raced My ERevo, I used to do 30 minute mains with a "cheater" battery swap. I used a series connector between the ESC and batts and started with a pair of 2s 6000mah packs wired in series(4s). I could get 20 minutes on this setup in the ERevo and when I came in for a battery swap, I pulled the series connector and one of the packs out and installed a single 4s 3700mah pack in its place to finish. Basically, I only had to swap one pack this way, which saved me some time. The 2nd "pit" is basically a trip through pit lane.

You just need to covertly install a high-power coil under the track and a matching coil/circuit in your vehicle that will pulse-charge your vehicle as you drive over it (albeit a very high power pulse). No battery swap needed! :smile:

You'd better shield anything else electrical in your vehicle though!

4s 6000mah for 20 mins makes sense, and when I say 18-19 mins for a 6s 3300, that would be to pretty well 100% DOD. I would only want to run 90% max, preferably 80%, to make room for future capacity loss, and just to give you that headroom if you want to wait a few laps to do a pit stop. But didn't the weight difference after you pitted make a difference in handling?

I never posted the 370 gram weight of the 2250mah pack I was looking at, that's 145 grams weight loss, enough to make a noticeable diff, I don't know.

Probably 2x 3300 6s packs might be the best bet then as far as weight, 2 pits, and cost is concerned.

$300 total for 2x 45C 3300 packs, or
$390 for 3x 65C 2250mah packs... hmmm

haha, yeah I could take my twin Tesla Coils and use them as transmitter and receiver! :mdr: Although only tapping ~100watts from the circuit might not cut it. :neutral:

It would if you put several of those coils throughout the track for multiple pulse-charges for every lap.

I left one of the 2s 6000mah packs in the ERevo and removed the other, along with the series adapter - the actual weight change and resulting impact on handling was minimal. The pit was basically removal of a single 2s 6000mah pack and series adapter and replacement with a single 4s 3700mah pack. I only had to mess with one side of the truck for the pit and didn't have to mess with the body at all(just push it out of the way during the pit).

Hmm, that reminds me of an idea I had with the side of the body so I could just lift a flap and swap the pack out without messing with body clips. I made a full under body shield made of Lexan, which acts as a mud guard and skid plate which allowed me to lower the suspension a bit, pretty well a truggy.

Something I just thought of, what do you guys think of a sway bar kit for the Revo?

A sway bar is a must for racing - without it the ERevo is either too stiff or has way too much body roll - totally different truck with sway bars. I didn't bother modifying the body on my ERevo - just pulled it out to swap the pack.

Oh well then I will have to get one. Even without it, all the top truggy guys drove my revo and commented on how balanced it felt and had good turn in. Which swaybar kit do you recommend? Tekno RC? Do you run the sway from and back?

I haven't used the Traxxas sway bar kit - the Tekno works well, though I always manage to lose the small set screws in the flanged rod inserts. I am sure either would get the job done.

I was using the 6s 45c 2700mah Thunderpower packs you mentioned. Great batteries. I ran them in my buggy indoors last winter and they were super solid for a 10-12 minute race. I wouldnt push them for 15 minutes. If you need 15min then go with the 3300 packs. For 25 minutes you will really need to load up on battery. I personally would rather do the battery swap than carry that load around the track. You could probably get 25 minute race done on one battery swap at the 13 minute mark using 2 of the 6s 2700 packs. I really never ran them beyond the 10 minute mark but Im sure I could have gotten another few minutes out of them with no issue.

I agree with Mike, The Hyperion batteries are super solid and priced very fair. Certainly cant go wrong there.

BTW: Those 6s 2700 packs are solid enough to push my truggy around the track for 10 minutes too. I dont race the e-truggy much any more but I ran it a couple times in the last year using those packs and they handled it no problem.

I'll get the Tekno unit then. Hey Jhautz, do you have any Eagletree graphs on those 45C packs? The mains at my track are 30 mins, not 25. Yeah, I used to use 6s 4200 G3 pack for ~20 mins, then swap out for a 6s 3800 25C Enerland Hyperion pack. wow, you must trash the throttle if you are getting the runtime on that much pack. I can get dang near 15 mins runtime on a 7s1p A123 pack at the track.

No. No eagle tree. I have one but, I gave up on worrying about the details like that. I havent even touched it in years. As long as the pack delivers the punch and doesnt puff when I beat on it its a good pack to me. :mdr:

As far as run time.... It depends on the track really. If its a tight track where you are picking through alot of technical stuff and you cant really lean on it then I get more run time, but if the traction is up and the track has room to let it run then I can blast through the mah. Same as anyone. The tracks around here tend to be on the large side so they do require some juice.

Yeah, that's probably why I have had higher runtime than you guys, our track has only 1 long straight, the rest is very technical and doesn't require much energy to keep the truck rolling on a steady pace.

So the race track is being completely redone into a different track layout this year, I think they are finishing it this weekend. I emailed my buddy, and track director to see what was up and tell him I'm coming back this year. He says the seasonal races, which run everyother Sunday, are going to be different starting this year, 3x 15min races for each class, with the two trophy races (2 day weekend races) that run once in June, and once in August are either going to be a 30 min or 45 min races :oh: I hope it's not 45 mins, that will be an expensive battery buy... I also am not going for Thunderpower, because you need buy some stupid balance port adapters which are going to be annoying to use... did you know TP packs have TWO balance plugs for packs over 5s?! It's time TP used JST plugs.

I got it down to two choices, which are dependant on how long those trophy races are...

30 min race = 3x Hyperion 6s 2600mah 45C

45 min race = 3x Hyperion 6s 3300mah 45C


Does anyone have any experience with TP 65C packs?

Good news, the trophy races are only going to be 30 mins for sure. A couple of guys were pushing for longer MAINS, but the majority said 30 mins if enough for marsheling; I know I wouldn't want to go for more than 30 mins either out there.

So I will be buying 3 of the 2600mah 6s 45C packs, plus they are selling the Sentry pack checker for $14.

$335 before shipping

Yea. 30 min is plenty for any race. I feel sorry for the poor Bmain guys that would have to marshal for 45 min. Marshaling a 30 min race sucks bad enough.

I can't seem to click confirm purchase for those Hyperion packs... I was just thinking, since only two races out of 26 races in a season are 30 min, and the other 24 are 15 min each, why not just go for the 65C TP 2250mah packs, for 8 mins a pack, and light weight to boot! 370 grams.

If I wanted to save money I would get a single 3300 65C pack for $170.

I know it might be a better idea to go for the 2600 packs, but I am feeling like what the hell, why not try these things out, and may as well use the C rating and get a small pack right?

http://www.skoffroad.ca/

Okay, there is the new track layout, they just finished yesterday. It looks like it is a bit faster than the old layout, and not as much tight elevation changes, which I will miss, like reverse banks and such.

JHautz, what would you do, buy two TP 65C 3300 6s packs for $340, locally no shipping... OR get the 3 G3/45C 2600 6s packs for $360 shipped? This is really bugging me.

The Tekno sway bar kit and Tekno RC axle carriers with 17mm adapters are on their way to me now. Hope they give the truck the needed edge to keep up with the truggies without popping pillow balls out at every corner, which is what the Ackermans on the carriers are for. First race this coming weekend.

Just curious, does Mike still sell the hybrid Revo 1/8 diff kit?

Hey guys, here is a pic of my new G3 EX packs! Each pack cycled the first time at 22mohm, 2nd time was 17, the 3rd was around 14-15, so I expect when I start putting a few good real discharges on them the iR should be down to 12mohm where they should be. I ran a couple should test runs only to ~70% DOD and wow do they already have awesome punch, the truck feels more balanced and I notice the weight difference for sure over my old packs. The Sentry balancer is a really nice gadget to have, especially for doing quick pack SOC checking, without hooking up to charger.

Also, I took the lexan plates i had undernieth the double shrink wrap on the old 4200 G3's and noticed they have puffed a bit and have what looks like dirt under the shrink wrap. That must be why they have lost so much capacity and puffed, and pack iR has gone up 50%. Check it out in the pic.

How would dirt creep it's way up into the shrink like that? Seems very unlikely to me.

yeeaah baby, I got 2nd place in Qualifiers yesterday, that was against 5 truggy guys! I had the 2nd fastest lap of ~42 sec, with my buddy in 1st place being a ~40 sec fast lap with a Serpent truggy.

Several younger guys are at the track this year with electric truggies and buggies, and I bite my lip when I see them buying thunder power 65C packs while running an cheap chinese brand motor/esc combo, or a MMM combo with cheapo packs... not to mention they are running these packs to 95% DOD!! Yikes, I am trying to teach them about lipo care and when a good pack/motor/esc combo will get you.

My little 6s 2200 G3 45c packs are running awesome, although I don't like the runtime (8-10 mins) depending how I drive, they are running wickedly cool, coming off at barely warm to touch (didn't temp them), but I would say ~15F over ambient. These other guys huge packs are coming off at 130F :neutral: (Zippy flight max packs).

:party: thats great

very nice!!

Thanks guys.

Does anyone know how to prevent the pillow balls from pulling out, I bought the Tekno hubs, but they don't prevent this particular problem. I was thinking two big 2.5mm set screws?

I recall there being a solution to this, but I can't remember who or where to find it.

use the little pillow ball reinforcement rings that you get with traxxas knuckles:yes:

No I mean the threaded end pulling or back there way out of the A-arm. the Tekno hubs are A+ man, these things are indestructible in my eyes.

Metal arms.

Well the only arms I would put on it would be the titanium flex-tek a-arms, but I hear they bent the hinge pins because of flexing.

Doesn't hcr make some billet for that. Or New Era?

Kcaz25, what do you mean by billet? Do you mean billet arms? Or some sort of mod for the plastic arms?

Here are some pics of the franken-revo, I couldn't believe how much of a difference the sway bar kit made and the light weight lipo packs. Lowered my lap times by 2 seconds from last year, can't wait to see what a truggy diffs all around will do.

No yeah, I mean 6061 t6 billet arms. That revo looks great!

what?:neutral:

Maybe I should have said, yeah. no. He did ask two questions.