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buying os 18tm

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nicholas655

nicholas655

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ok so i got convinced to buy an os 18tm engine for my revo 3.3 Ihope its as good as you all say it is! well what would be the best break in for this type of engine, i have the trinity pipe on for exhaust and 25% nitro , any suggestion??

any do's and dont'S for this ??
 
nicholas655 said:
ok so i got convinced to buy an os 18tm engine for my revo 3.3 Ihope its as good as you all say it is! well what would be the best break in for this type of engine, i have the trinity pipe on for exhaust and 25% nitro , any suggestion??

any do's and dont'S for this ??
Click to expand...


The os engines like the heat cycle method of breakin in my experience.

See this sticky thread below....I have used this to break in for 4 or 5 of these engines and they really pop....be sure to keep good time and leave it at BDC between cycle so the head forms right.

https://www.rcnitrotalk.com/forum/showthread.php?t=42716&highlight=heat+cycle+method


This is THE method used by the pros...
 
anybody else have more comments to help out, and i also noticed that there are 3 needles high ,mid ,and low plus idle screw, do i need to tune them all , (stupid questiopn maybe)and is it ok to break in with 25% nitro?
 
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nicholas655 said:
anybody else have more comments to help out, and i also noticed that there are 3 needles high ,mid ,and low plus idle screw, do i need to tune them all , (stupid questiopn maybe)and is it ok to break in with 25% nitro?
Click to expand...


Not a stupid question....the consensus is that if you break it in with 25% you will need to USE 25:....the same is true os 20%.

I use a mix that gives me approx 25% nitro and I break in with it and run it....

The book that comes with it explains the needles very well and what they do and when to touch them.....my experience is that you really only need to tune the high end and very slightly adjust the rest once that is set to your liking....but to each his own I am sure...

Nice engine you will be pleased.
 
cool , i should be getting it this week or the beginning of next , i am going to wait to do the break in because we just had a nice snow fall(damnit).can't wait to installit!! i'll try get a vid sometime showing it in action, thanks again for the info talonone
 
99.9 times out of 100 you will not have to touch the mid needle, I think its not really even worth putting on the carb.

Also for the most part you can go UP in nitro with little or no issues (basically just retune) but you cannot go down in nitro.

Your new engine should be easy to tune and last a while. Make sure you break it in slowly and it will be a great mill of you.
 
Just a heads up on that Trinity pipe. The exhuast port on the OS motor is larger in outside diameter than the Traxxas motor. The Trinity manifold will not fit without some Dremel work. It took me alot of Dremel work to get it to fit and left the walls around the section of the manifold that goes on the engines exhaust port very thin. I expect it to not last. Good news is the OS motor comes with a manifold that will fit so you can use that manifold and use some silicone exhuast tubing to connect it to the Trinity muffler (pipe or whatever you guys refer to that part as).
 
vbgagnon said:
99.9 times out of 100 you will not have to touch the mid needle, I think its not really even worth putting on the carb.

Also for the most part you can go UP in nitro with little or no issues (basically just retune) but you cannot go down in nitro.

Your new engine should be easy to tune and last a while. Make sure you break it in slowly and it will be a great mill of you.
Click to expand...

i willl be starting of with 25% and staying with that , and this time i will take my break in alot slower than last time,at least now it will run like a charm,

Hugger99 said:
Just a heads up on that Trinity pipe. The exhuast port on the OS motor is larger in outside diameter than the Traxxas motor. The Trinity manifold will not fit without some Dremel work. It took me alot of Dremel work to get it to fit and left the walls around the section of the manifold that goes on the engines exhaust port very thin. I expect it to not last. Good news is the OS motor comes with a manifold that will fit so you can use that manifold and use some silicone exhuast tubing to connect it to the Trinity muffler (pipe or whatever you guys refer to that part as).
Click to expand...

hey could i just use the same silicone piece that came with the stock exhaust and somehow use it with the trinity pipe??

i dont have a dremel and noone i know either,
 
Your easy option would be to use the manifold the OS motor will come with. I just measured and the manifold the OS motor comes with has a flange opening that is a full 3mm larger in diameter than the stock one.
 
Hey, just joined the forum and seems there are good peeps here. I burnt up my stock motor and want to upgrade and sounds like the os 18tm is the way to go. I noticed though that the stock motor is "3.3" and the os 18tm is "3.0"; is this a true upgrade (I am a newb to this and probably confused)?

Thanks in advance!
 
Xtreme Magazine put them both on the dyno and they are very similar with the 3.3 having a little bit more peak HP. The OS had a more stable and longer power curve than the 3.3 though.

All in all, they are pretty comparable. I do know the 18TM is a good engine. It tunes easy, holds a tune and runs like a screaming monkey.

With either the 3.3 or the 18TM, I'd suggest an aftermarket exhaust. The stock blue pipe is very limiting and I noticed a larger performance gain when I installed a fantom works pipe on my revo with a 18TM.
 
i run the trinity pipe with the os 18 and love it !!!!!!!!!!! i would suggest it to anyone
 
Thanks a bunch!

I guess I plan to replace my 3.3 since it would be the cheaper route ($130 replacement plan from Traxxas). Also, I don't plan to start racing any time soon, so unless the upgrade is out of this world, it may not be worth it at this point. I do plan to upgrade my exhaust though, and I will look into the fantom works pipe you suggested.

Any suggestions are welcome!
 

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