Okay, I was given a Traxxas Revo with many upgrades to the suspension, however no motor. So I've been reading up on a few engines: Dynamite "Big Red Monster 28 Mach 2, Xiangtat Original RC 1/8 Blue Black SH-28 4.57cc, and Traxxas 3.3 TRX Engine, IPS shaft with Pull Start. Question is will they fit with out changing the motor mount and which one would be the better choice? All come with pull start however I'm set up for Ez start..

Only engine that will fit, that you listed, without changing the mount is the TRX engne.


a good option is the OS .21TM, works with the stock mount.

https://www.towerhobbies.com/cgi-bin/wti0001p?&I=LXRTM2

My buddy is currently selling a nearly new Losi 3.4 on the bay. Item number 223438363708.
I can tell you from personal experience that the Losi 3.4 is a much better engine than the Traxxas 3.3. I have experience with both. Many 3.3, only one 3.4.

I have had many 3.3s. No problems with any of them, so I think they’re good engines.... They just need a little work to really get them to open up. I’m currently in the process of doing a mod job on a new 3.3 built from spares. One thing I did do was swap out the stock Traxxas rod with the replacement rod made by Sirio years ago. They made all sorts of parts for the 2.5 Traxxas engine; however the rod was the same between the two engines. I’ll have videos posted on YouTube of the hot mod 3.3 this spring.

My problem with the 3.3 is most all of them Ive had, had rear bearing failure.
Aside from that, the Losi 3.4 simply makes more power. My HPI Bullet currently has my only 3.3 I have left (with Avid ceramic bearings). My brother's HPI Bullet has a Losi 3.4. I simply can't keep up. Top end, they are very similar. The 3.4 has measurably more bottom end, however. The 3.3 isn't a "bad" engine by any means. I just prefer the 3.4 in every way. Aside from being extremely hard to find now..

The worst thing people do to make these engines fail - run them too cold and rich during break-in. The number one failure in the engine is the conrod. Nothing new here. Run it warm on a good fuel and you can easily get 10 gallons from one. I have a bone stock 3.3 that has over 9 gallons through it - 6 of which I ran in it (of my own blending). It’s my beater engine - I paid $15 for it. I’ve run airplane tuned pipes on it, 40% nitro, 0% nitro, and it just won’t quit. Same story with my last one (it was stolen along with ALL of my RC stuff a few years ago). With a better conrod, some minor crank work, and a bigger carb and they’re easily 1.2hp engines. Bone stock they put out 0.9hp.

The engine I’m doing right now has the Sirio rod and a modified & bored Macy 427 carburetor (modified to fit the 3.3 case, 7.2mm choke). Otherwise the rest will be stock Traxxas. I’ll document the breaking in, and some reasonable abuse in a Jato. How fast can a 3.3 really go in a stock Jato? Mine could only muster 61.5mph with stock 24/54 gears, 2-chamber resonator (stock), and a fresh 3.3 with 1.25 gallons of fuel run in it. I want to see if the Franken3.3 can get me to 70 and NOT pull a wheelie hitting 2nd gear.

I took out my big block slayer today (which is basically just a skinny Revo) and shot a couple vids. It made me think of this thread so I figured Id stick the links in here.
By the way, that engine mount is one of CKeithnitro's beautiful pieces.. it's going up for sale soon. The truck itself can't handle the power. It breaks stock driveshafts every other run and strips gears left and right.

https://youtu.be/WfKlLPjJuf8

https://youtu.be/DbrTqaaU_pM

That’s the problem with putting stupid power into a 1/10th scale truck. They’re not built for big block power. Traxxas isn’t known for building very strong transmissions. My stock 3.3 Jato eats 2spd hubs for lunch. I will have to lock it in 2nd gear with my drag mod 3.3 engine.

IMHO 1/8th scale engines belong in 1/8th scale trucks. Especially modified engines (and I don’t mean the eye candy mod engines some fellas sell).

I’m a biased jerk though. YMMV.

I agree some small trucks should have small engines. As you can see in those videos, the thing drives like an electric (power wise) and that's only an entry level dynamite 28 RTR engine in there.

My problem is, I can't leave well enough alone. Nothing I have is anywhere close to stock. Most of my RCs I own (the ones Im keeping and not selling off) are electrics getting converted TO nitro. It's a sickness, can't help it.

Post videos of your Jato once it's ready, eh?

I absolutely will. It should be a sick puppy. I’ll probably need to put foam tires on it to get any sort of speed from it.. or XO-1 tires. I have Revo tires on it now and they spin when it shifts into 2nd gear every time, and road rages spin like hard drag slicks. It won’t wheelie for beans because the tires just spin. I’ve gone back and forth between running it on road and off road. I even considered putting my Paris Racing Nova BX21 into it, but that was more work than it’s worth. Not to mention a waste of a really nice Nova from 20 years ago.