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sirio .27 break in help

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.21Rc10GT

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Hey people.

I just got a new sirio .27 racer for my t-maxx and i am ready to break it in. The instructions don't really say how to, so i need a little help. I have a temp gun and stuff. Good glow plugs and batteries, so I'm ready to go. I have a gallon of O'donnell 20% fuel so I'm good there too. I have heard the heat cycle is a good method, so i may try that, but I'm wondering how to do it tank by tank. If someone could help me out, i would really appreciate it. Thanks in advance.
 
copied from the S-Grid. this is the method I've found works best for me. I've used it on my sirio outlaw, OS V-spec, and Top .28 with excellent results every time.

The Bess method of breakin (also called the Heat Cycle Method)


From the very 1st time you start your engine, plop the car on the
ground & begin running it in a parking lot in 2-3 minute intervals,
tuned only *slightly rich* getting the temps up in the 200F range on a
normal day. Every 2-3 minutes, shut the engine down & let it cool
completely with the piston at BDC, and then fire it back up; continue
this cycle until you've run 15 min or so, and then bump up to 3-4
minute intervals. Vary the RPM and don't be afraid to get the temps
in the 200's. What you want is heat cycling of the components without
the incredible stress that comes with breaking an engine in when it's
overly rich & cold. After cycling the engine in this manner for about
20-25 total minutes, it'll be ready for the track and race tuning.

this method is not measured in tanks. its measured in time. in fact I've found my motors to be broken in within 2-3 tanks. after its completed you can go for your race tune, i like to go for about 90% of full power because like every method the motor isnt fully broken in until 1 gallon. after that you can go for your 95-100% power level.
 
Do you have the 21 coversion kit? If not you will need it as the Sirio 27 has a big block that won't go into the 2.5 or 15 MAxx Chassis.

I have the Sirio 23 an that is the biggest engine that can be placed on that chassis.
 
Yeah i have the extended chassis with the .21 conversion. I will try to break her in today, but its kinda cold... Is it ok to break in in around 40 degree weather?? Thanks
 
the method above is used by most..it is the best one i have seen so far
 
No but you can't break in an engine if you can't reach operating temperature.Keep an eye on the temps. Do you have a temp gauge? You may want to wrap that head in a sock if it is too cold. Good luck!

Jon
 
Yeah, i have a temp gun... and its now 42 degrees. I'm gonna wait till 10 o clock to see what temp we get up to! So, am i looking to get around 200 degrees? Also, would aluminum foil be better, since air doesn't go through it like a sock?
 
I needed more help on this... I havent continued break in because i'm waiting on a custom mount, but i do remember that when i was heat cycling it, it would die after like 30 seconds, and i could like pour fuel out of the exhaust. This sounds like its "too rich." Please help. All i have done with the needles was adjust the idle, so help would be appreciated. Thank you.

Also, my temp gun readings would'nt go above 100 degrees....
 
Sounds like you need to lean it up just a but if you are going to run her on the ground. Has the temperature improved? Are you running her on the ground or ploppoing her up on a stand or just letting it idle? If it is pouring out fuel profusely then you may want to lean it out
 
That was just the first to second tank, then i switched to the 1/8th scale clutch, and i'm waiting on a new engine mount. But, i was trying to run it on the ground and it would just die. Then i would try to take the glow ignitor off and it would die. Then i think since the exhaust is going at a slight upward angle, the fuel couldnt escape, so it killed the engine.

So i need to lean the top end right? since that is the main source of where the fuel comes in. right?
 
I would lean the top end just a bit. Since you are breaking it in it will need to run rich . BReaking in can be a PITA but done correctly you get a screamer!!!

Why is your exhaust at an angle?
 
Well, the pipe is a little long, so it sits over the reciever making it raised a little bit. I know i have to break it in pretty rich, but this seems overly rich.
 
Well on my Sirio 23 that Joneser4u has now I ran that rich as well. I mean that it barely made it to moving power. I just ran it in figure 8's then back and forth, but stopping every 3 seconds.I ended up having to run it a little more lean since it was butt cold out side.

Link a pic so I can see your exhaust set up

Jon
 
nice ride. It looks like you may be just fine with the way it is.
 
Yes you are overly rich for the heat cycle method, even for idleing... You want to be at least 180 in most cases, but if you are going to idle your engine on a stand than lower than that is okay. You should try to lean the engine in very small incriments until the temps creep up towards 200. But only run it for like 2 minutes then let it cool. Then do it again, and again, for 15 minutes of total run time. Then lean it a little more to get temps of around 230 ish, do that in 4-5 minute periods 2 or 3 times, then begin to tune for performance.
 
Very nice .21Rc10GT! I had missed this thread originally.
If my memory serves me correctly the instructions are about 1/2 of an 8 1/2" x 11" sheet of paper with limited instruction meant for advanced abilities.
Break it in ver 200 but not more than 230 for the break-in, heat cycling at half tank intervals. Let it cool all of the way down in between 1/2 tanks.
The mid needle on this .27 deceiving; the adjustment actually starts at the base of the bezel.
Bring it with you to the next Nor Cal Bash.
 
Never been to any... don't have a lisence....i will in about 7 months though! Definetally wanna tear it up with some other people, one of my friends moved away so i only have one friend to drive with now.

Thank you guys for the help, i really appreciate it.

Thank you guys for the help, i really appreciate it. I have a nova cooling head for the summer runs, so i think I'm set!
 

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