Racing brushless 1/8 scale

I just finished a brushless conversion on my Sportwerks Turmoil buggy. I went with a MM esc, a Feigao 7XL, and 3S and 4S Lipo.

I didn't have my 4S lipo in yet, so I ran the setup on 3S 4Ah lipo packs with a 14T pinion. I was getting 10-15 minutes of runtime. It was fairly cold last night and the battery was dead in my temp gun, so I didn't get any readings. I can say that my motor was hotter than the esc, so I'm going to assume that on 3S lipo, the 14T pinion left the motor a bit under geared.

Even still, I went out to the track to work on getting the kinks out of my setup. First thing I noticed was that the buggy had a tendency to nose dive when coming off of jumps. I was running the same suspension that I ran on the nitro rig. I figured that the back was just oversprung, so I switched to the stock springs and it got better. I think that I'm going to have to even lighter on the springs. I'm also running 40 weight shock oil. Perhaps a which to 30 weight will be in order for the colder weather we are having right now.

All in all is was a successful run. My lexan battery tray didn't survive and one of my packs got chewed by the spur. Thank goodness it didn't get all the way through the cell casing. I guess I'm going to have to go with my original plan for an aluminum battery tray. Other than that, I think that my setup is race worthy.

I'd also like to make some observations about the transition from nitro to electric. The first one was that I should have done this a LONG time ago. It was much smoother and controllable. Rather than having to blip the throttle to stay in the power band, it was more like using the gas pedal in a car. When I wanted the buggy to do something, I just issued the command. The torque is UNBELIEVABLE. There is one particular set of whoops that immediately follows a turn. It is a set of five and when the nitro guys usually run the track, they have to hit the turn just right to be able to clear the whoops. If you screw up sliding through the turn, you just have to suffer the whoops. With the brushless, all I had to do was take my time through the turn and just before the whoops, I hit the throttle and the buggy cleared them. We also have a jump that is about 3' high that is about 6 feet before a table top that is about 5' long right after an inclined 180 degree turn. Again it is critical for the nitro guys to drift the turn just right to have the momentum to make the jump to the table top. I was able to literally setup to right around 8' before the jump and hit it. Not only does it make the table top, but it clears it, landing on the opposite down slope.

[neweuser]

that is really good to hear. as far as your batt tray, you can go CF. I think the website is graphiteelegance, they sell angled pieces that may work well for you!

Yeah, I wanted to go with cf, but it appears that there is a shortage or something. Prices are through the ceiling. I'm going to check that out right now though.

Thanks.

neweuser,

THANKS for the info. Great prices and just what I was looking for. Can anyone give me an idea of how thick I should get it for a battery tray for my lipos?

[glassdoctor]

double post ha ha

Sounds good AA... kinda what I have seen too.

I suggest you go to 4s no matter what.... you can get the same speed and power with less amps pumping through system. A lower kv motor to match of course if the 7XL is overkill on 4s.

Heat of summer and a tall geared 3s setup may not work as well....

good job.... get a few guys converted and you won't have to be the lone ranger.

I have to do the fake pit stop too... about a 3-5 second stop and go. In our last trophy race I probably would have won had I not stopped. I finished 2nd, just a couple seconds back. I was a couple seconds behind the leader near the end of the race when I "pitted" and two turns later he wrecked and thought I was going to pass him.

I think it's the fair thing to do.

[neweuser]

Thank Serum, he gave me the link when I was looking CF. They are about the best! Serum is the Pro on the thickness. I was going to go with CF and decided not to. I already have one and decided to go the other route. Although I did pick up some CF for the other chassis I have from here, but don't remember the thickness. You probably wouldn't need more than a 1.5mm though.

Sounds great. I love to read stories like that. I've got one word for for your batteries: velcro. I use velcro on the bottom and a Gorilla strap over the top and they do not move whatsoever. combine that with some angled CF and you will have a bulletproof setup.

[glassdoctor]

Good point... I use a little velcro on the under the packs to. Good velcro under the packs and a velcro strap above... would take a horrendous wreck to lose them.

I still like to have a little side skirt of some kind as extra insurance too.

glassdoctor,

I am definitely going with 4S. I've already ordered the batts. :) I was just really impressed with the performance on 3S. Oh why did I wait so long to do this? My 7075 is coming in today, so I'll get on making the final version of my mount. Doing all of this mill work on my drill press is less than ideal though. Boy, do I miss my mill. What I really want to do is mill me a mount that incorporates the rear center diff mount. That, however, is beyond me capabilities right now. I can't get that accurate with my drill press.

As far as the motor goes, I'm starting to think that I should have taken your advise in the first place and gone with the 2000kv motor. If/when I get the Neu motor, it's going to be the 2000kv. I just can't see going wrong with that on the track.

neweuser,

I was going to make my battery tray out of architectural aluminum channel, in fact I ordered it and it's coming today. My apprehension is with the tensil strenth of the aluminum that the channel is made from. It isn't even 6061, so I don't know how hard it is. Gotta protect those lipos. If the aluminum it too heavy, I'm going with the cf. No choice there.

Cartwheels,

Now that's an idea. Velcro on the packs too. That should make them easy enough to get out, but should do away with the lateral movement. I ordered some gorilla straps last night.

[neweuser]

CF is light and durable. I think it was Serum who made a box for his batt tray out of CF, he said he was really pleased with it if I remember correctly. Try the aluminum, see how it goes.....if you don't like it, then you know where to go for the CF :)

[glassdoctor]

Oh... about the velcro on the lipo packs:

Never stick velcro on the bare cells. Don't ask how I know this ... :013:
It will mess up the cell when you peel it off. :035:

It's fine if the pack has shrink on it... but not without shrink. :007:

[neweuser]

Originally Posted by glassdoctor

Oh... about the velcro on the lipo packs:

Never stick velcro on the bare cells. Don't ask how I know this ... :013:
It will mess up the cell when you peel it off. :035:

It's fine if the pack has shrink on it... but not without shrink. :007:

Well, talk about a dead give away! LOL:005:

OK, so velcro on bare cells = a bad thing. Got it.

[glassdoctor]

Haa haa yeah I used some sticky velcro too... the cells still work ok, but it stretched and wrinkled the skin of the lipo.

I think it didn't do any real damage but I was a bit concerned... definitely not happy. And I didn't do it again. ;)