Works gotta know how to tune if your gonna get it. NITRO HEADS UNITE!

Had to work to fit it in my revo.

Well I've had this engine on my Revo for about a month or so now and I have already ran about 2 full gallons through it and it's holding up quite well. It definitely has more power than a STOCK 3.3. But I have a T-Maxx 3.3 that I installed a Big Block Carburetor on and a CVEC pipe and the Tmaxx is JUST BARELY faster in a straight line and out of turns. I'm using the stock clutch bell and spur gears on both the Revo with this engine and the T-Maxx with the Modified 3.3.I do have a Buku pipe on the Revo. So the power is also influenced by that pipe I'm sure but I'm happy with the engine. For a little over 100 bucks compared to almost 300 for an O.S. 21TM. This little dynamite just might find it's way on a couple of my 4-Tecs and maybe even an RS4. Don't get me wrong the O.S. engine is FAR superior to this engine but since all of the race circuits in my area no longer allow nitro. I'm back to just bashing and this engine is great for that. As well as the occasional park race between friends.

The break in procedure went smoothly after realizing that it was set FAR TOO rich from the factory. I had to lean it out almost a full turn to get it to start and idle correctly. And even with that it still completely SOAKED the rear of my revo during break in with oil and even after performance tuning still saturates the revo with oil. The break in procedure is almost identical to Traxxas's recommended procedure for the 2.5 and 3.3. So since I have that procedure memorized...I just used that. And have had no issues with the engine since break in. The more it gets used and broken in the easier it is to start and tune. Once broken in and tuned correctly this engine will idle all day and then go when you punch it. No hesitation, no bogging or stalling. Just power and fun!!!

Don't worry about the two 1 star reviews in any way shape or form. They just aren't familiar with big block style exhaust systems. Personally I'm glad they didn't reuse the bolt on exhaust header from Traxxas. It's more of a pain than its worth in my opinion. It DOES reuse the stock header from your 2.5 or 3.3 powered Traxxas vehicle but instead of using bolts it has an adapter plate so you can run a spring around the front of the block to hold the header on. Mine has NOT leaked once in almost 2 gallons of run time. And I beat the Pi** out of this thing every time I run it.

This engine is 100 times better then the 3.3 and it is easier to tune more power.had no problem install it but the speed censor dose not fit but all in all good buy

Very good engine.
1.Don't buy if u don't know how to tune an engine ...the adjustments they give you for tuning are completely wrong ...
2. I believe it's because instead of the c clip in front of the clutch bell, they put a screw that made the engine a little longer. ... I had to shave off piece of the transmission to accommodate. . 3 . U would need more hose .. cause u can't run the hose over engine n starter like the 3.3 . Now u have to run it around the bk of engine. .. ( but ur engine would run longer when it flips because of extra fuel in line )
4. If your exhaust don't fit tight on the engine manifold. Install a new one because it's gonna leak .. ( I used some grey silicone to seal mine )
Once u iron out the kinks your in for a good time! !