The Undistinguished Revo 3.3

[Thvts_Nvte]

Good Day, Party People

I never really made the conscientious decision to start modifying my Revo, and I really wouldn't expect this to become some crazy big block one off build with crazy rare and old school parts. This is just going to be my un-comprehensive build post for a relatively simple and standard Revo build. Basically just something I can work on and look back on if I need to reference something, feel free to follow along with me as I go through and build this thing. I'm not shooting for speed or durability, my driving is pretty tame and I think this thing is plenty quick as it is.

Currently Installed Mods:

- Swapped Over to a ELRS Receiver
- Deleted Opti-Drive
- Forward Only Conversion
- EZ Start Glow Igniter Removal

Planned Modifications (subject to change with time):

- OS11kr Carburetor (These are on backorder until July, unless I find someone who has one laying around this will have to wait)
- Swap over to an OS21??? (We will see about this one, it's expensive and I might just be happy enough with the 3.3 and a carb upgrade)
- Potentially a roll cage?
- Once I finally break an Arm I'll replace with RPM
- Stainless Hardware
- I would like to change the wheels that are currently on it for a different design, but the stock tires have held up really well even after a couple gallons
- Swap over to a single steering servo (Unsure which one to swap to)

So I've been wanting to start this thread for a while, more so for my own desire to just sit down and write for a little bit about my favorite rig, but I haven't really turned a wrench on this thing since I've had it outside of basic maintenance and a thrown clutch spring. Well, I finally decided to start tinkering with it a bit these past couple of weeks after purchasing a new transmitter and wanting to swap over my vehicles to said transmitter. The first rig in the hot seat was naturally my Revo, as it's my favorite in the stable and the one I use the most frequently outside of everything else. After receiving my Radiomaster MT12 I realized that I was going to need more than a 3 channel receiver if I wanted to get that Transmitter working with the rig. So I took to Amazon and ordered a Radiomaster ER5C 5 channel receiver. Of course, as I waited for my new receiver I took the Revo out only to realize I was having some hiccups with Reverse anyways - back to the internet to order a FOC for it. I had told myself the second I realized any issues with the opti drive system I was just going to pull it anyways, so naturally I did just that.

So, preemptively I started ripping everything out. The Opti Drive Sensor, now spare linkages and servo, and started cleaning up the wiring a little bit. During this process I decided I might as well just remove everything and give it a good once over.

Now, naturally this got out of hand. Many toothbrushes, and more degreaser than was actually needed has gotten us here. But it cleaned up well. I removed all of the extra sensors that would have otherwise gone to the now removed Traxxas TSM Receiver. A temp sensor, and speed sensor. I might as well mention that I had a wonky EZ-Start Glow Ignitor wire a few months back. So I have de-pinned that plug and completely removed the wire and swapped over to a traditional glow plug igniter. I really want to get rid of the remaining 3 wires for the EZ-Start system next, but I'm not fully sold on the idea of going over to a pull starter for this thing, I like being spoiled by the ease of use of it, not gonna lie. But having one less thing to lug around when I take this out would be a big plus so who knows?

During my obsessive cleaning spree I decided to go ahead and pull the carb off and clean it out, not a true rebuild as I replaced nothing. But cleaning out the needle jets and O-Rings I figured it couldn't do any damage. I'm still pretty sure that most of my runaways (cause I have a lot of them) are mechanical ones, I think my slide carb is getting stuck at WOT. Maybe I need to replace my throttle servo too....we all know Traxxas Servos are less than stellar anyways.

I didn't take a ton of pictures of the Carb rebuild - just a reference photo for when I put the thing back together.

Finally Some Mail!!!

Which was good timing as I had just re-installed the engine and was waiting for this and my ER5C Receiver (Which I also received in this shipment) so I yanked the transmission out too and cracked it open, which was surprisingly difficult and it fought me the entire time. I found this bent copper washer as the culprit. It's left me wondering if this is the reason why my transmission was giving me issues, or if I just broke things with my tiny ape brain. Who knows? I sure don't.

Deleted Opti-Drive For your Viewing pleasure.

And well, I followed the relatively vague, yet helpful instructions as best as I could. And you really do remove a ton of rotational mass from this thing going over to only forward gears. No need for a shift fork, and for whatever reason the reverse gears are metal, while all the drive gears are plastic. Which really makes a ton of sense to me - not. Well, everything still went back together without much of any issue or drama. I will say that it's nice that with this kit you get 3 really nice different block off plates. A plug for the now MIA shift fork, a plate for the Optidrive sensor on the transmission and a blank plate for the now open bay that would otherwise house the Opti-Drive unit itself. It really cleans up the look of the chassis.

And my ELRS 5 Channel receiver got installed!

Now, I'm not going to sit here and pretend I know everything about switching over to Radiomaster or ELRS. But the quick rundown is, it's tech from the FPV world with really good penetration (hence, no antenna) and it's all open source goodness. I haven't really dived into ELRS itself yet, but the receiver itself has it's own Wi-Fi chip and can do firmware updates through your home WAN. Which is pretty neat, I plan on tinkering with it a bit today. EdgeTX I have messed with a pretty good amount though and I built a setup for the Revo which definitely is still a work in progress. I've just been a bit distracted by my kids these past few days and haven't really gotten to finish up a few settings.

Enjoy the Jank picture. But, yeah. Quick run down on EdgeTX itself. It's another piece of software that's also open source and receives pretty frequent updates (relatively infrequent in terms of relevancy to us surface user plebians). A lot of people say EdgeTX has a bit of a learning curve, and although I think there is quite a bit of truth to that, I'm still getting the hang of it myself I don't think the learning curve is any more than it would be if you where to swap over to a completely new radio system regardless of brand as there is going to be a relearning process for a Sanwa, FlySky, Futaba, Spektrum you name it. The cool thing is, if you can think it you can do it with EdgeTX. Learning the how, and the syntax that's built in the system is where people tend to throw that stuff around but it's relatively easy if you tinker with it for a bit. I have a timer set for my fuel, managed to clone my CH.2 Steering Servo with my CH.3 Steering Servo (I don't have a way to make a Y-Harness at the moment and didn't buy one) I have a raise idle button, and two failsafes setup, one I engage myself and another if the receiver loses connection. Perfect for a 40mph 15lb Nitro Monster truck that isn't perturbed by the ground underneath it's feet! The ability to adjust the springs on the steering and throttle on the actual transmitter itself is real cool too, did I mention it has games built in? Its Gimmicky as all hell but my kids thought it was neat.

First Run with Forward Only and New TX/RX Combo

Outside of my Alignment being slightly out of whack now, which was a simple fix, the Revo started easier than it's ever started. I think the carb needed to be torn apart and cleaned since the beginning of time this entire time. Even on a pretty old Chinesium Glowplug it's running great - rich as all hell - but great. Tearing the transmission apart must have caused some adjustments to the shift point, it really doesn't seem too keen to shift, but it will. I need to spend some more time tinkering with it, hopefully I will get a chance to today and if not today I definitely will throughout the week at some point. It has quite a bit more go, it is noticeably more willing to get up and go, even with my lower nitro% fuel, does wheelies, and pisses off like idk what. I really enjoy it.

I only really got to rip it for about 15 minutes so far, most of which was idling. But the new transmitter seems super nice. Which I am excited to use more. My gas timer is a bit messed up but I can fix that with a little bit more tinkering. I'll keep you all up to date on that side of life. I think the next mod I'm going to do is swap over to a single steering servo, really don't want to buy the Traxxas recommended one - if anyone has a suggestion let me know. I would like to get rid of the redundancy, and it just seems like a hell of a failure point - and a pricey one at that.



Now I need to figure out what to do with all of these controllers and my other E-Waste

 

[easy rider]

I think you are definitely on the right track with loosing the opti drive. I like the FOC too. If you are keeping the 3.3 in it, your choice of carb is stellar. Close your eyes. Then open them. The difference you see when doing that is about the difference you’ll see in the 3.3 if you do that.

The OS .21 is a good choice too. But, running the 3.3 carb will get you everything a revo is capable of. While you’d never regret buying it, the 3.3 with the 11kr carb will run step for step with the 21TM. At a lot less cost. It starts just as easily. Runs just as good, and so far has been a dream to run.

Tires. I went with sledgehammer tires remounted for the 6s sledge. I did so because they are just as light as the stock tires and wheels but, they’ll gear your revo up perfectly. It’s going to be much faster over all. And so much quicker.

This is running stock pinion and clutch bell. And, you’ll find with either choice you choose for the power plant, both are so strong in comparison that factory gearing and wheel size holds the car back so much. You’ll run through the power band and be going 38-40 mph very quickly. Always leaving you wanting more on long wot runs. Put the sledge combo on it and run it with your rustler and maxx. Head to head. Because it’s going to be able to hold its own with that setup.

I have some videos in the nitro section showcasing how strong these trucks run with these upgrades.

I hope all that helps. And, it spurred me to get busy on my 3.3 revo build. I’m building one from scratch. I’m about 3/4” there on parts. Hopefully I’ll have it running in June. Good luck

 

[Thvts_Nvte]

I think you are definitely on the right track with loosing the opti drive. I like the FOC too. If you are keeping the 3.3 in it, your choice of carb is stellar. Close your eyes. Then open them. The difference you see when doing that is about the difference you’ll see in the 3.3 if you do that.

The OS .21 is a good choice too. But, running the 3.3 carb will get you everything a revo is capable of. While you’d never regret buying it, the 3.3 with the 11kr carb will run step for step with the 21TM. At a lot less cost. It starts just as easily. Runs just as good, and so far has been a dream to run.

Tires. I went with sledgehammer tires remounted for the 6s sledge. I did so because they are just as light as the stock tires and wheels but, they’ll gear your revo up perfectly. It’s going to be much faster over all. And so much quicker.

This is running stock pinion and clutch bell. And, you’ll find with either choice you choose for the power plant, both are so strong in comparison that factory gearing and wheel size holds the car back so much. You’ll run through the power band and be going 38-40 mph very quickly. Always leaving you wanting more on long wot runs. Put the sledge combo on it and run it with your rustler and maxx. Head to head. Because it’s going to be able to hold its own with that setup.

I have some videos in the nitro section showcasing how strong these trucks run with these upgrades.

I hope all that helps. And, it spurred me to get busy on my 3.3 revo build. I’m building one from scratch. I’m about 3/4” there on parts. Hopefully I’ll have it running in June. Good luck

I have actually seen those videos and am interested in doing that tire route when I need some tires, I haven't ran this thing on pavement literally ever, just grass fields so they still look pretty unused - but it's a wear item and once they wear down I'm definitely interested in going this route.

Go ahead and get started on your build! I much more enjoy working on this chassis than my slash and touring cars I've built in the past. You don't really need to do much to these things I feel like to get the most out of them, they're setup really well out of the box.

Are you still running the dual servo setup? I figure swapping over to a single servo and a pull starter (once the EZ start motor dies) It'll wake up even more yet again. I know some guys relocate their tanks among a few other things, but I'm just not too pressed to do all of that, I just want to knock out the failure points as they arise.

 

[easy rider]

I run a single servo. The red one from Traxxas. I’m pleased with it.

I’ve settled on a method for new breakin’s. I use the ezstarter until I have to remove the motor the first time after I’m running fully tuned. Or, it breaks. It started doing that to the point that made me decide the pull start. I’ll never run the ez-start as a permanent option again. Pre heat that motor good and warm, prime it, they start on the first pull. Seriously. It’s a a no brainer for me.

Yeah, I admire the guys with the skills and time to build and engineer these custom rigs. I would be doing it to if this was as important to me as hunting, fishing, trapping, atv/utv riding through the mountains. Basically being outdoors with family is my passion. This fills the gaps. Along with other cool things. I’m considering a dirt bike. I like them. I used to ride them a lot. But, I’m getting older. And, being a self employed General Contractor, you don’t heal good at 50.

Anyways, I got time to do what I can on the kitchen table. It’d be easier at the shop. But, I can’t hang with the wife at the shop. Do, I build these and run’em!!! They make me happy.

God is good gentlemen.