1BadS-Maxx

Hello,
I am fairly new to the Nitro RC world and need some advice. I have a S-Maxx 3.3 that I can't keep tuned to save my life, second engine, first one our fault. I followed the break in as instructed and it still will not run cool below 280 or so and if it is real rich 5-6 turn outto get cooler it runs like garbage and will not keep a tune, it has at least 2 gallons thru it. I am running O'donnell 20% and have been told it musthave an air leak. I have taken it apart and no metal shavings and could notfind any blockage or debries in it. I have put in a 4 wheel drive kit, steel axles, better clutch, 20 tooth bell housing, roll cage, Hi-tech 7955 titanium digital servo for steering, Maximizer beadlock wheels and Pro-line Chevron and Imex Swap dawg tires, RPM A-arms and shock towers, larger air cleaner and the Traxxas 2 chamber resinator for the 3.3and a few other things that I can't think of right now. I am thing about going to the O.S, 21TM but need to know if the 3.3 resinator will still be a good choice for it and what anyone thinks about the engine choice. We don't race just greenbelts and deserts. I am open for advice as this site came highly recommended.

Thanks

rcslsafut

i dont know about the .21 .but i just bought the os 18 tz for my old t maxx .i love it oooooooodles of power very easy to tune .
i have a os .15 cvr great engine too they are easy to tune very forgiving . im sure the traxxas resinator pipe would be fine ,the os .21
is a drop in replacement for your engine. imo os makes great engines ,i wouldnt be scared to replace 3.3 with os

1BadS-Maxx

Thanks for the info.

quietnas1

I have the .21TM IN MY jato and it is one hell of an engine. Gobs of power, great tunability, very easy to maintain. I would go for it. Money well spent IMO.

1BadS-Maxx

Thanks, looking for all the input I can get before I drop $300.00 on the engine.

Turboprop130

do you tune with a temp gauge?

1BadS-Maxx

Yes and no. I have been tuning by the smoke trail but it is still running hot-270-300. If I fatten it up to run any cooler it wont shift and runs poor.

guys2nv

You cant go wrong w/ a o.s. i have a revo 2.5r w/ the older o.s .18tm-paid 100 for it used w/ like a half gallon thru it-that was 2yrs ago(the .21tm is just a bigger case/block)-this thing will still ride wheelies all the way through 2nd gear and have tons of power. the main thing w/ nitro is u have to put afterrun oil in the engine after your done for the day-thats the biggest thing w/ nitros. wd40 will work to but ive heard that it can dry out seals-not good for nitro-sealing the back plate and the carb r crucial for it to maintain its tune. i like u got tired of the traxxas engines stalling and notholding a tune-the o.s will hold its tune(i havent touched the needles on my engine in over a yr) and it will run from full tank till its empty w/o missing a beat. good luck

1BadS-Maxx

Thanks for the input, just need to come up with the 300 bucks and will let you know how it went.

guys2nv

Nice, hope it works out-$300 is alot to spend just for an engine but u get what u pay for-just break it in properly and dont lean it out to much-richer is always better then leaner and always use afterrun oil after you put it away for the day/week(s).