Evolution of G2R Race Truck - Page 2 - RC-Monster Forums

Sylvester · 07:45 AM

Thanks for all the input guys. I am going with 14.8V 3200 mah cells, even though they are a bit pricey, i LOVE the fact that they are safe and have a quick charging process, and i all have to do is plug and play basicly. Will i have any issues with the fma lipos with my bk9920?

03.30.2006, 08:08 AM

I use the FMA Scorpion Packs in my Brushless E-Maxx and I can't say enough good things about them. I've always been a lower voltage BL guy, 14 cells before and now these 7.4v packs x2 now. All I can say is they certainly perform better than my 14 cell packs (and I was using good packs!) plus the weight savings allows you to do things with your truck not previously possible. The LVC hookup is simple and safe. Best of all, they were totally drop-in and race. No mods needed. (I use an 18.97 & a 10L or 9L) killer speed, way more punch and peace of mind. My advice, get one pair and two chargers, this way you can race the same packs several times per day. I had plenty of time between heats to let the packs cool and then charge them to 90%. At bigger races I can slow charge them to 100% with plenty of time.

starscream · 03.30.2006, 01:08 PM

Sylvester,
I just worked through the issue with the 9920 and skyvolt DPM's so I don't know if the scorpians have the same issue but I'd imagine they would. Nathan said they will be updating all thier DPM's but, to be safe, I'd contact FMA before you get the scorpians. Even if you did end up getting a set that didn't work, you could send it to FMA and get it corrected. If you buy them directly from FMA, you could request a compatible set for the 9920 and save yourself some time :027:

Serum · 03.30.2006, 02:55 PM

What was the problem starscream?

and Sylvester! somehow i missed this thread, nice revo! i've seen the GPM arms from Daniel, they are the ones you want on a revo.. Nice..

coolhandcountry · 03.30.2006, 03:08 PM

Yeah it is a very nice revo. I wouldn't mind testing driving it for you slyvester. ;)

Dafni · 03.30.2006, 03:28 PM

Leroy, you can come and test drive mine ;)

Nice G2R, Sylvester! I'm only beginning to taste the power of Lipos, but so far I love them. I will never buy Ni cells anymore. 5S is already "too much" for me... well, almost.

coolhandcountry · 03.30.2006, 03:45 PM

We will have to discuss this test drive further. You can take me over rene's for a test drive of his savage to. ;)

Dafni · 03.30.2006, 04:06 PM

I'll buy a lottery ticket tomorrow, with you in mind. Promise.
But I don't know about Serums Savy.... :005: I let him tell you about this.

Sylvester · 03.30.2006, 04:23 PM

Strascream, Are you sure that the 9920 will have problems with fma lipos? Thanks for all the compliments guys! I Was gonna use 5s lipo but i am confused with all the lvd/lvc stuff, and the fma has it all wired and ready to go. What will my runtime look like with 3200mah 10l ? (geared 18/64)

Sylvester · 03.30.2006, 04:28 PM

MacII, how long do your batteries take to charge?? What runtime do you see (we use same motor do we not? (10l) and what power supply do you use? (i want a power supply which i can hook both chargers up to)

03.30.2006, 05:57 PM

Honestly I use mine exclusively for racing, I got my LiPo's at the end of last year, raced 3 Sundays (4 runs per day) and I never pushed the limit of capacity so I can't really say how long you will get. In race conditions they were stellar start to finish for the 5 minute heavy throttle runs. This weekend is the first day of open practice so I plan to take them out for some more running and maybe with the temps outside so cool I'll run for more than 5 mins (I don't like to push the motor/speedo...thermal problems can result) Anyway I use the Competition Electronics 23 Amp Power Supply. The battery charge has been all over the map for me, 80% in 20 mins at 3C is not uncommon but I've started to lower the charge rate and still get to 80% in 30-35 mins. I've just made an adapter for checking voltage of the LiPo's while driving (using a Nomadio Sensor). Very slick.

Sylvester · 03.30.2006, 06:18 PM

Thank you macII, i should have a lighter truck than you (less bling/aluminum), 5 mins of hardcore running sounds nice, and since my motors a 10L not a 8L, i should get a min or so more of runtime, right? Any ways im awaiting a email from mike confirming that he will get me these lipos/charger, is there anything else i should consider/know before i buy them? Thanks for all the help, especially you , Mac. :)

Sylvester · 03.30.2006, 07:17 PM

Its been decided, im going for the 6400mah cells because mike has reccomended them, and because the 3200 are 2s4p, so the charger will not work with them, more runtime baby! :)

starscream · 03.30.2006, 11:25 PM

Serum,
The DPM connects in between the receiver and esc (9920 in my case)
The problem was that the signal was not getting from the receiver to the esc due to an issue with the DPM (signal voltage incapatibility I believe). At any rate, this issue should be addressed in new dpm's from FMA.

Sylvester
Those Kokam cells, configured at 2s4p, would be 12,800 mah so I'm not sure what you were trying to say exactly. You can't charge both packs at once though, this will require a second charger. I have two 6s chargers just for this reason.
I use the same power supply as MacII. I have to limit the charge rate to ~7.5 amps to run both chargers at the same time.
Both the 3200mah and 6400mah packs will work on the 2s charger.
For racing, I'd get the 3200's but if your looking for runtime, the 6400's will definetly do the trick.
Either way, I'd check with Mike and see if he has used his scorpians with a 9920 esc yet and let him know about this issue so he can address it when ordering packs from FMA.

crazyjr · 03.31.2006, 12:03 AM

I know Mike's run them with a MGM16016 but not sure about the bk's