O.S. 21TM-T .21 Engine w/T-Maxx Manifold

Quality is great however you will need to buy a different air cleaner setup to put in a T Maxx nitro 3.3.Everything was easy swapping out the stock 3.3 for this little powerhouse except a couple small things.
1) you will need a dremmel to grind a little bit off the base if you want to hook up the factory rpm sensor .
2)you will need a new air cleaner setup or a reducer as the carb hole is bigger than factory (I used the os 203 kit on one and a losi m8 on the other ) and they both worked equally as well )
3)It was hard for me to tune because id never tuned one before …I ran 4 tanks for break in then it took me another 4 tanks to get a tune I was semi satisfied with and another 2-3 to get it where i felt it was really dialed in!
4) you will need a GOOD wheelie Bar as this little Basxxxd has some serious power and or responsive characteristics compared to stock! I can’t keep the front down it wheelies at 1/3 throttle and has enough axx to flip this dude on accident frequently!!!
5) Tell your significant other to be prepared because it will create a definite chubby!

Love love love my OS TM engines!! Fantastic small blocks that scream and have way more torque then any other small block ever made

I purchased this engine for my Tmaxx 3.3 and these OS .21 TM engine is the best .21 size engine you can buy and install and run in Tmaxx’s. Its starts and idle very easy i followed the break in using Adam Drake method. Since the instructions dont give whole lot information. But once that done i tuned the engine and wheelies every time. Its built so well and all the parts seemed to be machined rather then cast which is nice. Only small complaint is the back plate uses Phillips screws instead of Allen hex but other then that This OS engine is the way to go for Any Tmaxx.

Best upgrade I did on my T-Maxx. Tuning is straight forward. Idles great. Low end torque is insane. Would recommend to anybody and purchase again.

I have had the o.s. 21tm on my tmaxx for 4 days and let Start off by saying it will hold a wheelie as far as you can see the truck. Everything was a direct swap. All I had to do was set the gear mesh and the throttle linkage. A+ to amain hobbys for the fast shipping and great price! Thank you for making me more addicted than I already was! ?