AE Racer

I finally have the time to break in my Sirio .12 (the roar legal version) after almost 6 months of waiting. Ive heard mixed opinions on break-in methods but I know that I want to run it around slowly on the first tank get it up to 200F right away. Should I heat cycle it by only running it in 2 to 3 minute intervals, this is reccomended in one of my rcca magizines. If I do heat cycle it at what tank should I stop and start running a full tank at a time. Is it alright if it takes a minute or two to get it up to 200F on the first tank? I'm not sure if it'll get up to 200F with the factory settings and it might take me a minute or two to lean it enough in small increasements up to 200F. Should I lean the highend needle to bring up the temp when running at low speeds, I dont think this will affect the temps at low speeds but I know that your supposed to tune the highend needle before you tune the low end needle.

heres the method that I think Im going to use:
tank 1: 10-15% throttle and up to 200F as fast as I can, shut the engine off after 3 minutes and allow it to cool then it start it up again and do the same thing until it runs out of gas, but stop it before it leans out when theres only a tiny bit of gas left in the tank.

tank 2: 15-25% throttle 3 minute intervals with cooling in between same as 1st tank.

tank 3: 25-35% throttle same as previous tanks 3 minute intervals

tank 4: 35-45% throttle same as previous tanks 3 minute intervals

tank 5: 45-55% throttle same as previous tanks 3 mintue intervals

tank 6: 55-65% throttle same as previous tanks 3 mintue intervals

tank 7: 65-75% throttle run the full tank and allow cooling afterwards temps around 200F

tank 8: 75-85% throttle same as tank 7

tank 9: 85-95% throttle same as tanks 7 and 8

tank 10 full throttle bursts for about two seconds and a range of speeds. The full throttle bursts will be gradually speeding up and not just nailing the trigger.

I would take it on the easy side for the next two or three tanks before race settings.

This is my first italian engine so any advice would be appricated, sorry for the long post.

Thanks in advance.

AE Racer

TTT I could really use some help from you motor experts this is my first Italian engine and I really dont want to mess it up.

Thanks

Old Skool

Kick that old-school technique to the curb. Idle one tank keeping the temp around 220F, using factory carb settings.

Allow to cool with piston @ BDC.

Replace original plug w/fresh new one.

Drive the car. Expect to fiddle with the carb during that first critical gallon. Tweak the high-end for progressively leaner HS needle settings, then run the hell out of it. It's an ABC engine and can take the heat. The question is, can you? Can you dig it?

EVOLUTION

Is it ABC or AAC??

AE Racer

Its abc, I want this thing to last so I want to do at least like 6 or 7 tanks of break-in. Is it really good for it to drive it normally right away? wont that put extra stress on the engine components? Anybody else agree with Old Skool or have any other opinions?

Thanks

Old Skool

Difficult as it may seem, idling 6-7 break-in tanks through a competition engine will actually wear it out faster. ABC engines need HEAT in order for the p/s to mate up properly. Let me show you by example: when I got my first ABC engine (HPI .12R SC, essentially a Novarossi CX-12), I idled the engine slobberingly rich...there was a huge puddle of fuel outside the pipe stinger and I could hold my hand on the heatsink for the longest time. Now, that engine lasted for what seemed like forever, but was always slower than other such side-exhaust engines.

I heard/read about some 'new' break-in procedure and decided to try it, idling a single tank (above 200F) and then going ahead and running it. Lo and behold, every single new and rebuilt engine I have subjected to this technique has been the fastest I have ever owned. The several-tank idle method was fine back in the day of ABN engines, but manufacturing tolerances and materials have advanced lightyears since then. Go ahead and try it, trust me, it works!

AMGRacer

I concur with OldSkool. Mayby running a lot of tanks very rich will make your engine last longer, that I cannot say for sure. But if you run them in fast they seem to be faster .

AE Racer

I didnt mean Idleing I meant running around slowly for the first tank getting the engine temp up to 200F right away to prevent premature wear and increasing speed every tank after that, until around the 7th tank when you hit some full throttle bursts. Then I would run it around with these settings a few more tanks before leaning it out to race settings. Is this what you mean or do you mean run it like it was broken in after the first tank, that seems like it would be harmful to the engine. I definitly wouldnt even think of idleing 7 tanks. I was planning on doing no idleing at all. Even the manual says it should have at least 15 minutes of break-in type running before normal use, that would be around three tanks and Im sure they dont want your engine to last. So I guess no one thinks heat cycling is a good idea just run it in full tanks?

theRED5

I broke in my new Sirio 3P Saturday, I ran 3 tanks at idle, then drove 3 tanks so rich that the car would not shift into 2nd gear, then I tuned for performance. Then today(85-87 deg with 95% hunidity)(30% Byron's Race formula 3000) at the race, I ran some checking temperature, and keeping it at about 230F deg., in the 1st heat I ran out of fuel before the 5 min race was over. So, more tuning, leaning the bottom end so that the screw is even with the housing on the low side, ended up turning the high end in a full turn from the way it came out of the box. Always making sure it was blowing smoke.

Result: fastest lap times ever, 30 min A main win.

AE Racer

congrats on your win Red5

I wasnt going to do any idleing and just start off running around very slowly, would it be best to idle or run around very slowly on the first tank? From what Ive heard from you guys and many other places you should run it slowly on the first tank rather than idleing. Ill be running 20% odonnol in it and it'll probably be 75 to 90F when I break it in.

theRED5

I've always broken in engines differently but this one's modified and that's how he wanted it done.

I usually run them wide open, so rich that the RPM's stay low. 3 tanks like that then start leaning, then richening, when the head starts to get hot/warm, for 3 tanks then just tune to win. Always monitor the temps, I try and keep my engines under 300F deg, and when on the track look for smoke. And use Marvel Mystery Oil afterrun.

chachi

I recently broke-in a Novamega SX12. The manual said to start running it from tank 1 on, so no idling. I ran it rich but kept the temp at around 200-220. For the first few tanks, I ran 1/4 to 1/2 throttle bursts with the car coasting in between. After the 3rd or 4th tank, I slowly started leaning out the high end while getting deeper into the throttle. After the 8th tank, I started tuning both the high and low end until it was hauling. Two gallons of 25% later, and it feels like engine is getting faster every time I run it. Compression is still unreal.

Couple of tips before you start the break-in procedure:

1) Disassemble the engine and make sure there are no metal particles left over from manufacturing (extremely rare, but brutal on your engine if present)

2) Coat all internals with some after run oil, or at least some fuel, before you fire it up for the first time. Starting a new engine dry will only cause premature wear.

AE Racer

Thanks chachi, I think Im going to break it in the way you did. It dosnt really have any break-in instructions so Im just going to use the method which seems most common which is running it on the first tank and increasing speed every tank and leaning it a little once I get to the 5th or 6th tank. I dont really feel comfortable taking apart the engine, but I going to be taking off the head to flip it around so I can use it on my ntc3 so Ill take a peak inside. Ill definitly lube it befor I start it I dont think I could turn it over if I tried.

Old Skool is this the method your talking about running it right away, but at slow speeds and increasing speed each tank.

If Im running at low speeds and its not hot enough should I lean out the HSN? I know you'd Lean out the LSN usually, but arent you supposed to tune the HSN before you tune the LSN?

Does anybody know if MC-59's work in the Sirio? I remember hearing they were the best plugs for the Sirio but I just thought Id make sure that the Sirio takes long plugs.

AE Racer

Oh and so nobody thinks I should heat cycle it by running in 2-3 minute intervals like reccomended in rcca?

AE Racer

ttt