Planning Revo V2, to use stock tranny, C. diff and RCM motor mount

[Finnster]

Video is ready Enjoy!

[Serum]

Pancake madness..

balooning anyone?

Great vid Finnster!

[jnev]

Great video. It really shows off the power there. When you checked the temp under the body, was the motor 118*F or the esc?

[Finnster]

Originally Posted by ***RC***

Great video. It really shows off the power there. When you checked the temp under the body, was the motor 118*F or the esc?

That was the caps on the ESC actually, they tend to run a bit hotter than the actual heatsink.

[Finnster]

First to bump my Revo build up thread! Thank god the forum is back as I didn't want to re-write all this!

Updates are that the std center is back in (CD sidelined for now) but I looking to go to a Hi-voltage setup. Namely 10S A123 (33V) and a 1515/2Y Neu (1100kv). The controller will be an MGM 9032. Sweet.

[Finnster]

My vids from the RCM bash. Truck held up very well and lasted for two days on that track. Looking at the # of DNFs, I was happy to last throughout, even tho I had my setup all wrong and a steering problem that was giving me fits, Just couldn't make it around the corners half the time and ended up on the lane bumpers.... On the jumps, even when I landed flat, its was so bouncy is would bounce onto the roof

Oh well, still took home 3rd in the MT class and 2nd place in the brushless open. I'm happy for my first race and learned alot, so I'll be much more ready next time. Still working on the repairs tho. :) The HV setup is nearly complete, so some other goodies to come.

[Mallanaga]

you're nose diving every time you jump due to the auto brake or whatever it is from your ESC. the motor is slowing the wheels down, which is the same as putting your breaks on with nitro in the air. nose dive!!

if you stay on the thottle, or manage to cut your drag breaks to zero (aren't you running stock brakes with a oneway in the tranny, though?)... hmmm. just try staying on the throttle when you jump. don't peg it, but keep it steady, and you shouldn't nose dive.

i've also heard good things about wings helping the revos in the air quite a bit. grab one of those tekno wings, and get some air!

[Finnster]

Originally Posted by Mallanaga

you're nose diving every time you jump due to the auto brake or whatever it is from your ESC. the motor is slowing the wheels down, which is the same as putting your breaks on with nitro in the air. nose dive!!

if you stay on the thottle, or manage to cut your drag breaks to zero (aren't you running stock brakes with a oneway in the tranny, though?)... hmmm. just try staying on the throttle when you jump. don't peg it, but keep it steady, and you shouldn't nose dive.

i've also heard good things about wings helping the revos in the air quite a bit. grab one of those tekno wings, and get some air!

Actually I was having to nail it just to keep the nose not all the way down. It really wasn't wanting to correct much in the air. The balance is not that off tho. Part of it as well as the F springs were too soft, and I have no motor drag brake, its all done by the mechanical brake, and I have it set to release w/ any input of throttle. My driving looks pretty bad, but you can't really tell how much I was fighting it. Things would have gone nicer w/ a better setup up veh.

GeeRegs pic fpr example of the susp softness in action:

[gtxracer]

The announcer is hilarious! You guys hit each other more than the rails, in the air no less. Nice job!

[Finnster]

Updates:

I've replaced the MM/XL setup with a high-voltage, hi-efficiency powerplant. I am now running a MGM 9032 ESC and a Neu 1515/2y/F (1100kv) driven by 33V 10S A123s or 8S Lipos. Geared 16/36 on std 2nd gear. Top speed is geared for low 40s (~42 mph on radar.) I have room to gear up still, but this is plenty fast.

Basically the aim was to be able to keep the A123 cells and go to a hi-eff setup, and not have to up in cell count. In short, any setup that draws more than 70A really needs to have a 2P config to not overly draw the cells. That leaves a 10S1P or a 5s2p like I had. Going the HV route, I am able to run the cells I want, but also run @ higher eff which translates to more power to the ground, less wasted heat, and a very smooth and powerful system.



The old system drew nearly 120A @14V to make ~1650W. However, the XL setup was only maybe 70-75% eff. Meaning less than 1250W made it to the wheels, while 100s of watts were lost as heat. It was easy to overheat motor w/o careful driving.

Now I make 1650W with 61A peak @ 27V+. At ~95% eff, that translates to nearly 1570W to the ground an only 80W lost as heat.

===> Extremely powerful and cool running system. The motor never gets very warm. The esc is dead cold.

Here is a torture test. I dumped the full pack in less than 8min. (Normally I get ~20+min bashing.) WOT thru long wet grass up and down a hill non-stop. Doing this w/ my XL system would over heat the system fast. I'd see 180-190F on the motor in minutes. Here, final temp is only 112F. The ESC was 85F at the end. Ambient temp was 65F.

Even at that the temps only spiked at the end trying to drive on the dumped pack. Mostly stayed ~100F. This has been a dream system so far. :)



Here's a few setup pics. Not a whole lot has changed from before. The Esc is long, so some care was taken to place it right and protect those huge caps. I re-did the batt straps to be easier and much stronger. The RCM Bash was tearing up my old ones w/ all those roof landings. lol So far I'm very pleased. I've also mounted a RC8 wing on a mugen MBX5T stay which isn't shown.

[Finnster]

Here's some pics from the last race this weekend, RCMTRA Worlds @ Barnstormers. I did pretty well overall and I was happy w/ the truck this time around. Qual'd 2nd in MT, lead the main for a bit, then made some errors and fell back to 4th. doh! Also ran in BL class and took home 2nd place trophy.




[/QUOTE]

[jnev]

Nice job!! Thats the same track that the RCM bash was at, right?

[Finnster]

Originally Posted by jnev

Nice job!! Thats the same track that the RCM bash was at, right?

Yeah, same basic layout, but they redid the end of the track to accomodate the RC MT side by side races. The enormous triple was toned down a bit, where the last jump was more a tabletop leading to a turn, but it was still a good jumping track.


Also, I went up on the springs from the bash. I ran golds in the front w/ 60wt oil, and in the rear I went upto tans w/ 70 & then 80 wt. It was doing really well overall, some more tweaking should get it in.

The rear is still a bit soft, even w/ preload all the way down. The spring rate seemed pretty good, but the intial rate was a bit soft. I may try some blks, else go to the 120mm springs to take off a bit of the pre-load.

I also recieved my TrueRC 8S 3200 15C batts right before the bash. I ran them in the mains and was pretty pleased, may more power then I can use. On the 10 min main I used up 1600mah, including a bit of driving around during the warmup. The batts are 650g, and can certainly be sized down a bit for shorter mains, but you never know until you run it. Should do a 15 easily. 8s A123s may work good as well.

[Finnster]

Short video of the race:



My father in law filmed it.. its 3min long, but the race was 7min+.. that's how much I had to cut out as it got a bit crappy at points. Too bad as Alex and I had a really good battle going. He kept wanting to zoom close in, but the trucks move so fast it was hard to keep up like that. Lots of thanks to him tho, so be nice