BL Revo conversion almost finished!
 

Hey guys, here are some pics of my Revo 3.3 conversion I am just finishing working on (wasn't much work). It's got a 1512 3D (1700kv.), Quark 125, 7s1p A123 pack (going to try it and see if it will handle, if not, will use 2p). I made a simple alum. plate of the one side of the chassis for the pack to be strapped to, hopefully it will stay on!

The truck will weight in at roughly 9 lbs. RTR. So it will be very light and agile... hopefully it will preform as good as it weights.

Here are some more pics of the tranny mod.

looks great

Looks very nice!

:lol: I suppose you're right, it is a MT after all.

The Revo is looking very nice.

In the last picture of your 2nd post, it shows the two screws you put into the gear. I am doing this mod right now as well, but can not figure out how to take that metal plate off... :oops:? Yes, its pathetic, I know. But I have never taken the tranny apart before. I am also installing the wide ration gear set, which is the other reason why I need to get the metal plate off of the plastic gear.

Let me know. Thanks.

Thanks guys, it's nice and clean yeah, looks good so far, I hope to keep it that way! I am waiting on my shrink wrap for the pack... thats the 7s A123 pack in the one pic, it's hard to see I know.

KK, you have to take the U shaped clip off the gear next to it, then slide out the pin on it and take that gear off... then you should be able to slide this gear off, and then the metal plate. Very simple. Got it? :wink:

Pretty sure I got it. Will the "U" shaped clip just come right off? Do I just lift one side of the "U"...? and then the other side will come out too?

Thanks for the help.

What U shaped piece? Are you talking about the C clip on first gear?

The C clip yah I guess thats what you would call it more like. Isn't that the idler gear? First gear has the one way bearing in it, I am pretty sure.

Jnev, you can use needle nose pliers or a flat head screw driver to get it off, it will pop off.

Looks pretty good!! Great job :smile:

Here is a pic with Quark installed w/ cable weave over.

Cable braiding looks very nice..... until the first time it gets dirty. :)

Were you planning on running just 7s1p then? The maxx was 2P correct? What was your motor and amp draw again?

Looks good Zero... don't forget the vids... videos are awesome... like your video Finnster..

thanks again,

I am trying just a 7s1p pack for starters, it will definitely be able to power it, but with how much voltage drop.

With the Maxx truck (good remembering Finnster :yes: ) I had 2p yes, and there was very little voltage drop with the max amperage of around 70 amps, sometimes 80, the lowest I saw the voltage go down to was ~21 volts (from 23v nom.), so 70 amps should be easy for 1p. I am guessing the V-Droop will be around 19.5v with this truck at 70-80 amps, as I geared it a little lower (13T from 15T), and it is lighter than the Maxx truck as well, so taking that into consideration. The runtime should be around 15 mins, as it was at least 30 mins with 2p pack, and geared higher, and heavier.

I will get it finished tomorrow (when heatshrink arrives for pack), I will post some pics for sure! :rofl:

Aqwut, unfortunately I don't have my Sony Cybershot anymore! (video capable) :no: I traded my sister for a Canon Rebel SLR, which is what these pics were taken from.

Yeah I'd like to see what it does, tho I thought the A123s were rated for 70A max discharge according to the spec sheet. I draw 120A+ from mine (2P), and they get to ~110F as the pack dumps, so we should see. That's fairly close to max and they are not getting too warm. Truck looks great tho

Hey guys, here are some pics of my finished E-Revo 3.3 conversion.

My computer has not been working for the last few days so I could not post the pics... but anyways here they are! :yipi:

Some more...

Anyways, I ran it for the first time today because of cold rainy weather and it performs great! It feels very light and agile compared to the maxx truck with 7s2p... I was running 7s1p this run. I used the eagletree in there as well and found the voltage drop at ~70 amps is around 19 volts (from 23v nom.) so right around where I thought it would be, but obviously lower than what a guy would like. :oops:

With the 7s1p, it looks to have about 1200 - 1300 watts of power, and the pack weights a tad over 500 grams which is very light.

One thing that is very different about the Revo is the suspension feel, it's just so much different from Maxx trucks, both the feel and adjusting.

It was geared for 40mph top speed today. Sorry, no video for now! :no:

That is one CLEAN Revo conversion. Looks like it should stay that way :angel.

If you haven't tried out those tires yet, you're gonna love them.

Excellent conversion bro. Nice to see all the radio/bec gear fit into the stock servo box. If I ever ditch the manual brakes I may rearrange mine like this. (I looked at putting the futaba fasst rx in the micro servo slot, and still looks like it a bit too big.)

Good to hear about the A123s performance as well, nice at 500g too. 2.7v/cell@70A isn't bad at all. I was getting 2.8v @60A. These things are discharge monsters. Could you put some some ET data when you get a chance as well?

Last Q: How removeable is the Q125 over the shocks? The MGM I bought is quite a bit bigger than the MM I have, so I may need to move it above the shocks, but haven't thought of a secure mount that's ez to remove for diff and shock service.

I like. Not to repeat the same question already asked, but how exactly is that esc mounted- looks great & very low profile.

Nice job man, very clean.

Only one problem: You need more capacitors on that Quark. :tongue:

That's not a Quark, that's a capacitor with a Quark attached to it. :smile:

Thanks guys! I am very happy it turned out, it looks killer! :intello:

-Yeah, 70 amps on only 2300mah in a truck cannot be used with lipos, they simply would fail, presumably. I am still impressed by them in that respect, in their current 'handling'.

-My Quark125 is mounted on top of the screws of the shocks and a little lip on the tranny, and is held down by a reusable zip-tie. I am thinking up something different to do with the controller however, as it is a little 'rigged' at the moment.


What's Nitro, I am glad you like my Quark mod... :wink:

Here is an Eagletree of part of the run.

I looks like the voltage will be at roughly 22 volts at top speed, maybe higher, so top speed should be right around 40mph, can anyone confirm this?

I just did another run on the truck, and took the temps this time.

Runtime was very good, a solid 15mins with only 7 M1 cells, not bad at all! :oh:


Temps:

motor: 108F
esc: 80F
pack: 102F

The temps are very good, but, also it was not hot out today, so that helps.

15 minutes on 1p - wow, that's pretty darn good! That means you are averaging 9.2A current draw with peaks somewhere around 60-70A. So, that means 212w average and an estimated 1500w burst power.

Yeah, I am as impressed as you are, I was waiting for it to dump... just kept going, all I was doing was runs back and forth in the yard, just shy of hitting top speed. But the temps I was getting, amazing! I thought the batts would have got warmer than that! :oh: This was with low 'power' setting, and softest torque setting.

The average current is right around 9.2 amps like you said, but the peak power is somewhere around 1300 watts more like, that's what the eagletree shows.

So now I am going to finish up my 2p pack for more power and runtime... so I will have two packs, one for racing if I ever get a chance to... I am 2 hours away from the nearest one, and they are only in a couple months of the year.

Well, that 1500w estimate was generous. I typically use between a 6x-7x multiplier and it usually works out very close. 9.2A x 7 = 64.4A burst. That makes 1487w, but that's assuming the voltage is 3.3v/cell, which I'm sure is not the case. Assuming the 7x multiplier is right, 1300w would equate to about 2.8v/cell under that load. Is that about right?

I'm curious because I still want to make that runtime calculator/lipo selector page for my site and need all the sample data I can get. BTW: Could you post your eagletree results in that thread? It would help a lot.

You bet, it IS about 65 amp bursts, I saw a single 70 amp burst so far of the two runs I have done.

What other info would you like? Any other setup info? like gearing, weight?

I will post my 7s2p pack eagletree as well on that thread, and I will post a new eagletree plot when I get my new 7s2p pack made (as soon as I figure a good mounting).

But so far, it appears like it's about 2.7 - 2.8 v/cell under this kind of burst load at roughly 65 amps, and I think 70 amps is the limit that you want on these cells, me thinks as far as good performance goes, and temps.

Actually, I am going to do a full run with the eagletree and see if I can sqeeze it all in there, so you have more data to work with.

Be back in a bit. Also, check out my 'current electric vehicle conversion' link soon, I will update the pics with the motor mounted... :yes:

Basically, I just need the info requested in that thread. With all the data, I want to do the following:

- Calculate estimated burst current based on reported runtime on specific battery type/size, truck type, top speed (which auto factors gearing, tranny, tire size), and weight. 6x-7x average amperage multiplier seems to be pretty good for a ball park figure, but I'm sure it will vary depending on the above factors.

- Calculate mimumum lipo specs (mostly C rating) based on the estimated burst current so people can choose a lipo setup that won't be overloaded.

- I'll probably also throw together a section (or even a seperate page) where the user can enter their current runtime and battery specs, then enter desired runtime, and the script will calculate the needed battery.

That sounds like a great addition to it Brian! Just what ppl need! :party:

This run was done in thick grass, and it looks like this pack can deliver 1550 watts! It's not in the snapshot I am posting but later on in the data graph.

I will post this here, and on the other thread, kk?

I can sure feel the decrease in punch though, going from 2p to 1p pack, but it's still pretty good feel of power as I can wheelie at speeds up to roughly 32mph, of the ~<40mph top speed.

Also, I checked out the cumulative mah of the recorded run, it shows up as 2500mah! Every A123 pack I have had has always been quite a bit over th rated cap, which I'm not complaining about! :mdr:


The max amps was 85 amps too, maybe I will post another one with amps instead of watts?