will this work in a e revo?

[grenade6]

hey guys im building my first electric so i need to know if this will work. it gona be a e-revo (with a e-maxx tranny) i us for bashing and on a track after i build one. so i was thinking of using 2 8s a123 2300 mah 26.4 volt packs wired in parallel with a MGM Compro 160 amp, 24 cell brushless car controller http://www.rc-monster.com/proddetail...MM160243sHCS01 and Neu 1515 2.5d/F Sensorless Brushless Motor http://www.rc-monster.com/proddetail...5_2.5dF&cat=20 .
i was also wondering if i need extra cooling for the motor? something like this http://www.rc-monster.com/proddetail...d=RCM01&cat=20 and if i do what size will fit on that motor? i also have no idea what kind of wire conections to us so i was just gona us the Dean's Ultra Plugs and wires in the battery section of rc-monsters store. well thnx for your time and ansers

[What's_nitro?]

Well I can tell you that's gonna be one powerful setup!

I really like 5.5mm bullet connectors for high power stuff. If you're gonna use Deans connectors, I'd use a complete set on each individual wire. I would also recommend using 10 AWG wire or larger.

[offroader]

I'm also doing a Revo BL mod and need some help! Not sure what type of gear to buy I'm going to use a 12L Feigao motor with a BK 9920 esc. What type of gear do I use on the motor 5mm bore 32 pitch pinion gears? or 5mm bore, mod1 pinion? What is the difference and why do they have so many?
What size ( # of tooth) would be best suitable for a Revo? I was planning to use the stock tranny that comes with the Revo or a Emaxx tranny if I can get a hold of one.

[grenade6]

well i cant help you much but i used this http://scriptasylum.com/rc_speed/_top_speed.html to see what gears im gona us. good luck

[lincpimp]

Revo uses a mod 1 spur gear, so you will need a mod 1 pinion. Pinion size will depend on what batterys you will use. A 12l feigao has a kv of 2048, so 4s lipo or 14 cells would be a decent setup. Using the stock tranny and std tranny gearing, I would suggest and 18 tooth pinion. Then you could vary the spur gear as traxxas makes a 36, 38, and 40 tooth spur. The 18/36 gearing with stock tires will give you about 40 mph. Here is a copy of the speed calc with the numbers I used to find this. I used 4s lipo as the battery, but it is very close to 14 nimh cells voltage-wise.

Differential Ratio: 2.8461538461538462
Transmission Ratio: 2.2941176470588233
Other Ratio: 1
Spur Tooth Count: 36
Pinion Tooth Count: 18
Total Voltage: 14.8
Motor KV: 2048
Tire Diameter (inches): 5.75
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0.0172
Spur/Pinion Ratio: 2 : 1
Total Ratio: 13.05882 : 1
Tire Circumference (inches): 18.06 inches (458.83mm)
Total Motor Speed: 30310.4 RPM
Vehicle Speed: 39.7 MPH (63.78km/h)
Effective Speed Rate: 2.68mph/V (4.31kmh/V)
Effective KV Value: 2048
Motor Torque: Amperage not specified...
Final Torque: Amperage not specified...

[offroader]

Thanks for all the help on this lincpimp. Where do we use the 32 pitch pinions? on Emaxx Trannys?

Originally Posted by lincpimp

Revo uses a mod 1 spur gear, so you will need a mod 1 pinion. Pinion size will depend on what batterys you will use. A 12l feigao has a kv of 2048, so 4s lipo or 14 cells would be a decent setup. Using the stock tranny and std tranny gearing, I would suggest and 18 tooth pinion. Then you could vary the spur gear as traxxas makes a 36, 38, and 40 tooth spur. The 18/36 gearing with stock tires will give you about 40 mph. Here is a copy of the speed calc with the numbers I used to find this. I used 4s lipo as the battery, but it is very close to 14 nimh cells voltage-wise.

Differential Ratio: 2.8461538461538462
Transmission Ratio: 2.2941176470588233
Other Ratio: 1
Spur Tooth Count: 36
Pinion Tooth Count: 18
Total Voltage: 14.8
Motor KV: 2048
Tire Diameter (inches): 5.75
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0.0172
Spur/Pinion Ratio: 2 : 1
Total Ratio: 13.05882 : 1
Tire Circumference (inches): 18.06 inches (458.83mm)
Total Motor Speed: 30310.4 RPM
Vehicle Speed: 39.7 MPH (63.78km/h)
Effective Speed Rate: 2.68mph/V (4.31kmh/V)
Effective KV Value: 2048
Motor Torque: Amperage not specified...
Final Torque: Amperage not specified...

[suicideneil]

Originally Posted by offroader

Thanks for all the help on this lincpimp. Where do we use the 32 pitch pinions? on Emaxx Trannys?

Generally speaking yes. Since the Emaxx uses 32 pitch gears its easier to use 5mm bore 32p pinions on the motor (such as a Feigao or neu etc). If you prefer though you can get whole new spur/slipper assemblies that use mod1 spur gears, so then you would use the mod1 pinions. Mod1 gears have larger teeth so dont strip as easily as the 32p gears, but its a case of budget/ personal preference and how good you are at setting the mesh really.

[offroader]

Originally Posted by suicideneil

Generally speaking yes. Since the Emaxx uses 32 pitch gears its easier to use 5mm bore 32p pinions on the motor (such as a Feigao or neu etc). If you prefer though you can get whole new spur/slipper assemblies that use mod1 spur gears, so then you would use the mod1 pinions. Mod1 gears have larger teeth so dont strip as easily as the 32p gears, but its a case of budget/ personal preference and how good you are at setting the mesh really.

Thanks for the info on clearing up the mod 1 with 32p pinions who would carry the upgrade kits for emaxx conversion from 32p to mod 1? Do they sell a mod 1 pinion gear that replace the stock 32p pinions on the emaxx.

grenade6,

Have you ever seen an A123 cell? I'm just asking because those things are huge and heavy. They are about the size of an alkaline C cell battery and weigh 70 grams each. You're talking about 2.5 pounds of one brick (literally) of a battery pack.

Anyway, if you are going to run that many cells in a truck, I'd shoot for a lower kv motor. Perhaps something in the 1100 to 1200 kv range. I run a 1515/2.5d in my 8ight T on 18.5v and it'll do 50 mph. I think that running the 2.5d on that much voltage for any sort of extended running might result in lots of heat.

I'd go one of two ways. Either the 1515/2.5d on a 5S2P A123 setup, or your chosen voltage with either a 1515/2y or 3d.

[grenade6]

lol ya iv never seen one and the last electric i used was from radioshack and it cost me like 100$ when i was 12 lol. the bad news is that i bought the batteries this morning (off the net) so i cant really change my mind now but i havent got the motor yet so ill take a look at those motors. nad thnx for the info even tho i now know i bought bricks

[suicideneil]

Originally Posted by offroader

Thanks for the info on clearing up the mod 1 with 32p pinions who would carry the upgrade kits for emaxx conversion from 32p to mod 1? Do they sell a mod 1 pinion gear that replace the stock 32p pinions on the emaxx.

http://www.rc-monster.com/gears.php

They have all the different flavours in the RCM shop- MOD1 1/8 bore & MOD1 5mm bore, plus 32pitch 1/8 bore & 32pitch 5mm bore. You can work out the equivalent sizes using the gear calculator:

http://www.scriptasylum.com/rc_speed/_gear_calc.html

For example an 18tooth 32pitch pinion is equal to a 14 tooth Mod1 gear.

[kenkamm]

Hi folks. My First post.

I built myself a E-Revo by using some parts out of my Trex-600 heli. An align 600XL motor (1700kv) and the Align 75A ESC. I used the pistix gizmo to make the aircraft ESC work. I made my own motor mount. I kept the stock tranny and mechanical brake and even the reversing system and optidrive. I built a carbon shelf on the right side which holds 8S A123s. I relocated the receiver, receiver battery, and optidrive to a carbon shelf above the front shocks. Surprisingly the left-right balance works out very well. The truck has lots of power and plenty of run time to keep me happy. Before I geared it down I clocked it at 48 MPH with Proline Road Rage tires on it. I also have a set of Moabs for it and have geared it down to more manageable speed. I really like having the two speed still working because I can do some nice crawling in first gear, then on flatter ground it will kick into second and really take off. I may upgrade to a Neu motor and proper ESC at some point, but this setup works very well and the align motor and ESCs can be found used very cheap… 60-70 bucks for each. Top it off with the $100 Dewalt battery A123 source, and you've got yourself an E-Revo with serious performance for modest cost.

I've found that the airplane-style ESC and 8S1P A123s yield very good performance. I think 2P would be too heavy. I get at least 10 minutes of bashing time with mine, which I think is good enough considering it only takes 30 seconds to change the battery. Better off keeping the truck light IMO.

Cheers,
Ken

[suicideneil]

Welcome to the forum kenkamm! That sounds like a nice setup, and the inrunner motor debate is still on-going so any thoughts/numbers/temps etc you have would be useful in determining what works well in any given setup. Got any pics/link?

[kenkamm]

Here are a few pics. Next upgrade: Neu 1515/2.5D.

I don't have any temp information for you guys at this point. I can tell you that if I put the Moabs on, and run hard in grass, the ESC and motor get pretty darn hot. (But, no hotter than it did on the helicopter.) But it's still overgeared for that kind of use. I am not a hardcore basher... I tend to crawl around over stuff, then do a few high speed runs, slow back down a crawl around a bit, back and forth. I don't just go out and hammer it continuously until the battery is dead. The performance is pretty amazing right now though. Except for a little bit of a jerk at throttle tip-in from a dead stop, it will crawl at a fraction of a MPH nicely. Then if I floor it, even on pavement it will light up all four road rage tires. It used to flip over backwards even at higher speeds until I put the wheelbase-extending rear arms on it.

[zeropointbug]

kenkamm, that is one nice Revo man!

What motor is that you are using? kv?

I am assuming that is an A123 pack? Is it 4s2p, or 8s?