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Old 07-09-2007, 12:59 PM   #1
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Default [B]who broke in their motor this way????[/B]

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 mannerfor about 20-25 total minutes, it'll be ready for the track and race tuning. I realize this method goes against the old-school "idle on the box" routine, but you'll be amazed once you've completed this break-in routine, your OS will still have amazing pinch w/out sticking at the top AND your OS's compression will last far longer than it will with the "old school" method.

You say you run the engine at "factory settings" for the first FIVE tanks? That alone causes lots of stress, as the factory OS settings are very rich on every OS I've ever owned or tuned. The piston & sleeve haven't expanded to operating temps, and every time the engine turns over, the piston slams into the pinch zone at TDC. The not-so-surprising result can be a cracked con-rod at the crank pin--that's where the majority of the stresses occur as the engine turns over. I've only heard of about 6-8 OS engines breaking con-rods, and they're ALWAYS during the first gallon...and almost every time it's because the guys have performed the break-in procedure you described. Doesn't seem like a mystery as to why it's happening. Drawing out the break-in routine really stresses the engine & actually wears away compression along the way. This method I've outlined will feel weird at every step, but after you try it once, you'll notice a big difference in your engine's performance & lifespan.

Hope this helps; give this break-in method a shot--you have nothing to gain except longer life & more power
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Old 07-09-2007, 01:56 PM   #2
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I've been using this basic method, less the short intervals, since my days flying airplanes as a kid. It's very effective, and seems to parallel the method my most trusted mechanic used to break in full size Air Cooled VW motors. By letting it idle too cold, you're wearing it excessively. However, one of my team mates uses the idle on the box technique, and it works for him.
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Old 07-09-2007, 02:23 PM   #3
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I have been combining the two methods. I idle on the starter box but I pre heat the engine with a heat gun to 200f and wrap the head in foil so it will idle with a rich setting but still stay hot (~200-220f). After 3 or 4 -5 minute intervals I start running on the ground lust to apply a little load to the bearings and rod. After a couple of runs (light throttle) it's pretty much ready to go.
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Old 07-10-2007, 08:38 AM   #4
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how does the combining of the 2 methods turn out for u, do the motors that have had the 2 method break in run really strong
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Old 07-10-2007, 09:16 AM   #5
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Just to let you know about the WOT method - don't do it!!

I have 2 OS VZB'S both new from the same shop. I ran the first one in by the first method you desribe. This engine is now on its 3rd gallon and it rips. No wear on th rod. The only additional thing i did was warm it with heat gun whiel running in.

The 2nd one i heated up with the gun, ran 1 tank at idle then 6 at WOT. After that tuned for performance.Sunday this engine snapped the rod with less than 1 gallon on it.

i know which method i trust at least with the VZB's. I also ran my RB in this first method way and thats fast as well
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Old 07-10-2007, 09:24 AM   #6
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Quote:
Originally Posted by jatoman1992 View Post
how does the combining of the 2 methods turn out for u, do the motors that have had the 2 method break in run really strong

Yes. It makes a good break in with a nice tight piston/sleeve fit, the pre-heating makes it really easy on the rod and the foil guarantees that I achieve the proper temps (at a nice, slightly rich setting so there is plenty of oil passing through) so that I am not wasting the engine's life by running it below the temps that it will be run at once race tuned. I am fully convinced that this is the way to go.
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Old 07-10-2007, 09:33 AM   #7
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I use the same method as Davidka and have had terrific sucess.
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Old 07-10-2007, 09:45 AM   #8
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same thing here, heat it up to 200+ and start it running rich for about two tanks, keep it rich then start running the car at up to 1/2 throttle bursts keeping temps up but letting the engine cool completly(internally) between tanks. Ive had 0 problems.
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Old 07-10-2007, 10:36 AM   #9
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cool thanks
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Old 07-10-2007, 12:09 PM   #10
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I do the above break in with some minor differences. I run an entire tank at a time and by the end of the second tank I take them to the track and put a conservative race tune on them and go for it. Usually by the time Ive run 6 tanks through an engine Ive used it in at least one qualifier. Ive been doing this for 5 years now and only once have I snapped a rod and that was on a Rossi engine with 2+ gallons through it that completely grenaded due to a runaway.
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Old 07-10-2007, 01:57 PM   #11
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I run all my engines in this way.It takes a long time to do it properly but when its done they absolutely fly and i also found they last longer.
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Old 07-11-2007, 09:55 AM   #12
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Please give credit to the website that you got this from http://www.johnnycoolguy.com/JCGR/ma..._break-in.html

With that said, I have recently have broken in my crt (force .28) this way. I am very happy with the results. I have to say I did let it run two idle tanks before i started this process.

Just make sure you use good clean fuel, and when you are in the cool downs, make sure your piston is BDC.
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Old 07-11-2007, 01:22 PM   #13
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I use the heat cycling method as well. I have no complaints as my motors run really strong and have a very good life as well.
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Old 07-11-2007, 09:48 PM   #14
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i like the heat cycle method and i like to run them very rich and run only at an idle. sounds weird i know.

i always run them super rich let them idle around 120-130. bump up your epa so it will stay running. then blast it with a heat gun while its idling. this will bring your temps up to around 220-230 and your motor is still extremely rich and no stress is being put on the engine by revving it. i idle about 4-5 tanks that way then run a tank around the track easy to seat the bearings good then rip on it. i have been doing them this way for a long time now and have had no issues. best of both worlds if ya ask me.

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Old 07-12-2007, 10:14 AM   #15
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Any engine that I have heat cycled like above has been a great engine and lasted me awhile.
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