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View Poll Results: Built motor break-ins Easy vs. Hard
Easy break-in 72 26.37%
Hard break-in 201 73.63%
Voters: 273. You may not vote on this poll

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Old 08-23-2010, 10:24 PM   #1
NWSTi-wa
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Default Built motor break-ins: Easy vs. Hard

Which do you prefer?

Here's a link to cobb tunings recomendations:

http://www.cobbtuning.com/info/?ID=3475

Here's a well known site that promotes a "Run it hard" break-in:

http://www.mototuneusa.com/break_in_secrets.htm

I'm not saying cobb tunings method is more of an easy break-in, im just saying it's not nearly as agressive as the motomans method. So I want to use this thread to learn of other methods and how they work for everybody.

My only experience with engine break-ins has been from 2 cycle engines in the karting world and when I broke those engines in I ran them on the harder side, similar to the motomans advice.

Let's use this thread to post your experience with your break-ins.
Hard or easy? Post which you prefer and how it went for you.


Edit: sorry if there is already a thread about this, ive searched and searched and have not found anything that's similar to the topic of this one.
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Old 08-23-2010, 11:46 PM   #2
JF824
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To break in I put 1000 miles on my motor (ACL Bearings, Manley Rods, Wiseco Pistons, GSC S1 cams) with zero boost. So far I have 8000 miles and its running very well. I ran about 21psi for about another 500 miles after I broke it in. Then after that I've been running 27-28psi for about 6500 miles with no problems. Oil comsumption is barely anything over 3000 mile intervals.

For my first Subaru (05 WRX) I had no break in and just beat the ***** out of the car. It lasted 100k with 80k @ 20psi on a Big 16G. I traded it in with no problems.

My stock STi motor I did the same and it lasted 20k before I had to rebuild it but I didn't break the car in. I bought it used at 8k. I spun a bearing and I think it was due to a *****ty tune.

IMO go with the break in period recommended by your builder.
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Old 08-24-2010, 02:03 AM   #3
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When watching some of the cool "how things are made," type shows on Discovery HD, Science Channel, etc... Watch how the OEM's break in their engines.

The Audi R8 engine is built by hand and put on an engine dyno and put through it's paces.. Hard. That thing gets red hot, then shut down, and installed into the car.

I believe Chevrolet had the same method on some of their performance models too.

That said, this is a touchy subject and I have no real opinion.
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Old 08-24-2010, 02:17 AM   #4
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i ran my motor soft for 1000 miles, at around 7000 now and other than needing a tune i have no issues.
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Old 08-24-2010, 03:42 AM   #5
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I don't agree with cobb's idea of running bascially no boost or load on the engine till 500 miles.

I followed mototuneusa's idea on my STI and the motor turned out to be a freak motor with an insane amount of TQ with a stock tune. I would never drive a new motor easy nor avoid boost. The rings seal by having force press into them. Driving around like grandma isn't going to do that.

All OEM's run their higher end model engines very hard prior to installing like mentioned above.
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Old 08-24-2010, 04:39 AM   #6
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I think that the best method is to run it hard increasingly, so starting with hard acceleration up a low rpm, the release, repeat it for a while, thenincrease slowly the rpm, and so on, up to the rev limiter. With boost the break in will be more fast (maybe too much?), as there will be more pressure in the combustion chamber, pressing the rings against the walls.
During the hard acceleration the pressure in the combusiton chamber force the rings on the bores, allowing a good and fast break-in, then closing the throttle decrease the pressure inside the chamber, allowing some oil to be sucked by the rings, cooling and cleaning them. This is how break-in high power 2t engines, and it made quite sense also in a 4t engine.
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Old 08-24-2010, 09:31 AM   #7
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Go mellow for 500 miles then beat it, if it breaks it wasn't meant to be, if it doesn't, shes a runner ............
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Old 08-24-2010, 09:42 AM   #8
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Quote:
Originally Posted by project_skyline View Post
I don't agree with cobb's idea of running bascially no boost or load on the engine till 500 miles.

I followed mototuneusa's idea on my STI and the motor turned out to be a freak motor with an insane amount of TQ with a stock tune. I would never drive a new motor easy nor avoid boost. The rings seal by having force press into them. Driving around like grandma isn't going to do that.

All OEM's run their higher end model engines very hard prior to installing like mentioned above.
Quote:
Originally Posted by masterx81 View Post
I think that the best method is to run it hard increasingly, so starting with hard acceleration up a low rpm, the release, repeat it for a while, thenincrease slowly the rpm, and so on, up to the rev limiter. With boost the break in will be more fast (maybe too much?), as there will be more pressure in the combustion chamber, pressing the rings against the walls.
During the hard acceleration the pressure in the combusiton chamber force the rings on the bores, allowing a good and fast break-in, then closing the throttle decrease the pressure inside the chamber, allowing some oil to be sucked by the rings, cooling and cleaning them. This is how break-in high power 2t engines, and it made quite sense also in a 4t engine.
Just FYI that's not really how piston ring seal occurs. Its got allot more to do with heat cycles and friction.
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Old 08-24-2010, 10:05 AM   #9
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1) Check that water is filled
2) Check that oil is filled
3) Check that fuel is filled
4) Turn it over and idle for 10 mins to check all the fluids stay where they should
5) Drive the car out and rag its' arse off
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Old 08-24-2010, 12:24 PM   #10
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orly..... i see my post is gone.


anyways...
I let the car idle up to temp and turn it off. I do this 3 times as it allows for heat cycles to go through the engine. I drove it up to 300 miles with no boost just to wear in the bearings. Then after that I started boosting to seat the rings.
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Old 08-24-2010, 01:20 PM   #11
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I voted easy but I dont 100% agree with cobb's easy..I say...
1)let it warm up
2)shut it off
3)let it cool completely back down
4)warm it back up
5)drive around out of boost for 20mi and do as much engine braking as possible
6) change the oil
7)put it under boost no more than 5psi/4000rpm's for 100mi
8)same as above but no more than 8psi/4500rpm's for 300mi
9)same as above but no more than 10psi/5000rpm's for 500mi
10)same as above but no more than 12psi/5000rpm's for 800mi
11) same as above but 12psi with a couple redline pulls and more engine braking for the 1000mi
12)drive it like you stole it
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Old 08-24-2010, 01:46 PM   #12
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I've always been a hard break in guy. First few minutes listen to the engine, check gauges, make sure all is right once up to temp and then shut down, change out the cheap oil and filter (in case of any debris in the motor). New cam break in happens during this time frame.

Then fire up, get the fresh oil to temp and romp on it a bit. I still engine brake when breaking it in.

Certain ring materials do however have different needs.

Last edited by Homemade WRX; 08-24-2010 at 09:29 PM.
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Old 08-24-2010, 02:28 PM   #13
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I just drive it like a normal person. I don't go wot making 20+psi of boost but if I have to merge onto a highway, I will give it some stick.
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Old 08-24-2010, 07:45 PM   #14
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Quote:
Originally Posted by WheredUgo? View Post
Just FYI that's not really how piston ring seal occurs. Its got allot more to do with heat cycles and friction.
High rpm, water/air cooled 2t engines are done in that way. 15 min of break in, then run it hard as it can. The 2t pistons, rings and cylinders are much different, and for sure on our engines the break-in can't be only 15min, neither in only one session (that was only an example), but it's the pressure in the combustion chamber that load the rings, forcing them on the bore (and made friction). With no load (too easy break-in), there isn't enough pressure to make friction with the bore, and if the rings aren't seated before the first hard run, there can be serious damages, as bore glazing, too heat on rings and pistons (yes, pistons cool itself also via the rings), etc.
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Old 08-24-2010, 09:43 PM   #15
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It seems this debate comes around every 1-2 years or so. A few years ago when I rebuilt my first subaru motor (EJ25D) using all oem parts (wasn't cheap) I read tons of threads and online how-to's. It seems to be the norm to put the engine through it's paces a bit. Don't purposefully beat the $hit out of it, but make it work.


~Josh~
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Old 08-25-2010, 04:54 AM   #16
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I know lots of 400whp motors that were making it less than 100 miles on the motor, often less than 20 miles on the motor......

They may not pass emissions, but none of them have ever lost a bearing.

Piston? Rod? yes. but never a bearing.
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Old 08-25-2010, 06:31 AM   #17
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I start mine up, get it to operating temps, drive around for like 5 minutes no boost. Change oil and filter. Then drive 50-100 miles 7-10 psi. Then drive 50 miles 10-15 psi. Change oil and filter drive 20-21 psi WOT.
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Old 08-25-2010, 10:15 PM   #18
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thanks to all of you who posted up with your results/thoughts. its helped me a little!

keep it up!

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Old 08-26-2010, 12:09 PM   #19
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Serious debate.

I too have seen those behind the scene shows of ferrari or GM ect..but, I will follow my builders reccomendations.

Start, check everything, idle to temp. Change dino oil and filter.

Start, check everything, idle to temp and drive 100mi change oil and filter.

Start, check everything, idle to temp and drive 500mi and so on.

Engine breaking as much as possible and no highway driving for the 1st 1000mi.
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Old 08-26-2010, 05:20 PM   #20
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Quote:
Originally Posted by project_skyline View Post
I don't agree with cobb's idea of running bascially no boost or load on the engine till 500 miles.

I followed mototuneusa's idea on my STI and the motor turned out to be a freak motor with an insane amount of TQ with a stock tune. I would never drive a new motor easy nor avoid boost. The rings seal by having force press into them. Driving around like grandma isn't going to do that.

All OEM's run their higher end model engines very hard prior to installing like mentioned above.
Quote:
Originally Posted by jkopinga View Post
1) Check that water is filled
2) Check that oil is filled
3) Check that fuel is filled
4) Turn it over and idle for 10 mins to check all the fluids stay where they should
5) Drive the car out and rag its' arse off
All the guys i know that build motors just run it long enough mix the oil with a assy lude then run the hell out of it and change the oil after about 500 miles
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Old 08-26-2010, 06:40 PM   #21
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Quote:
Originally Posted by JF824 View Post
To break in I put 1000 miles on my motor (ACL Bearings, Manley Rods, Wiseco Pistons, GSC S1 cams) with zero boost. So far I have 8000 miles and its running very well. I ran about 21psi for about another 500 miles after I broke it in. Then after that I've been running 27-28psi for about 6500 miles with no problems. Oil comsumption is barely anything over 3000 mile intervals.

For my first Subaru (05 WRX) I had no break in and just beat the ***** out of the car. It lasted 100k with 80k @ 20psi on a Big 16G. I traded it in with no problems.

My stock STi motor I did the same and it lasted 20k before I had to rebuild it but I didn't break the car in. I bought it used at 8k. I spun a bearing and I think it was due to a *****ty tune.

IMO go with the break in period recommended by your builder.
i cant tell you how wrong that is. you need to create vacuum in the cylinder, and in order to do this you need boost. you have maybe 100 miles to break a engine in properly with glazing the walls. you sir are lucky. no offense to you, but do not take this persons advice.
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Old 08-26-2010, 06:47 PM   #22
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Quote:
Originally Posted by Cbgrandtheftauto View Post
I voted easy but I dont 100% agree with cobb's easy..I say...
1)let it warm up
2)shut it off
3)let it cool completely back down
4)warm it back up
5)drive around out of boost for 20mi and do as much engine braking as possible
6) change the oil
7)put it under boost no more than 5psi/4000rpm's for 100mi
8)same as above but no more than 8psi/4500rpm's for 300mi
9)same as above but no more than 10psi/5000rpm's for 500mi
10)same as above but no more than 12psi/5000rpm's for 800mi
11) same as above but 12psi with a couple redline pulls and more engine braking for the 1000mi
12)drive it like you stole it
while this is better, you need to create inconsistencies. by doing this you are going to create hot spots on the wall.


for example. the worst thing to possibly do to the engine is to start it, dont boost and go on the highway.

the best way to break an engine is what motoman suggests.

again, no boost + no load = bad ring seal.

Here is my suggestion. warm the car up, take your car to your local pimp spot, drive around down town for 10 minutes. the constant changing of gears and engine breaking is good for the car. again, always vary your rpm. then take it for a mild cruise boost 5-10psi, and let the engine decel. keep doing this. all you are doing is knocking the burs off the rings and the cylinder wall. creating a nice seal

as far as the oil changing is concerned? meh everyones picky. i just use poopy oil for the first 100 miles, change it at 1000 then 3000. then every 3k afterwords.
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Old 08-26-2010, 08:54 PM   #23
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The first few miles were put on my motor by the tuner on the dyno. I know he was boosting it, and lots of engine breaking. Then I took the car home, drove it 100 miles keeping it under 3500rpm, boosting to about 5psi in every gear, then I would engine break it down to almost a stop and start accelerating again. After 100 miles we drained the oil and cut open the filter to see what was in it.


Then I drove the car for 1000 miles pretty normally. I still kept it under 4000rpm and never boosted over 8psi, while engine breaking every time I had to decelerate. And I made sure to vary my RPMs a lot.. people following me were probably pissed because I would speed up and slow down over and over again. Once again we drained the oil and checked the filter for bearing material.



After that it was time to tune and put it through its paces. I would consider it an easy break in, but there was always a little boost and lots of engine breaking.
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Old 08-27-2010, 01:12 PM   #24
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When I worked at Garrett we had many engineers that came from auto manufacturers, most told me the break in most used (in a vehicle) is:
Start vehicle
warm up at 1500-2000 RPM
after oil temperature reached operating temp (about 10 mins after water) shut down
check all fittings connections make sure everything is stout.
after engine cools down about an hour start engine wait for oil temp to reach operating temperature again.
Drive vehicle slowly make sure you have all gears and oil pressure is 100%, and temperatures are good.
Now the break in
Maintain 20-25mph in second gear. Slowly open up throttle to 50% until 55mph is achived(or about 5000rpm)
then let off throttle. (still in second gear)
Let engine braking slow vehicle back down to 20 mph. Repeat 4 times.
Now open up to 75% and 5000 rpm and once again engine brake down to 20mph.(4 times)
Now open throttle to 100% and up until 6000rpm.engine brake once again down to 20 perform this about 6 times.
(some transmission with very short gearing may perform this cycle in third gear)

I have been told after this cycle engine is almost broken in. (depends on ring material) I have run this cycle many times. Works good but I never had any intramentation installed to verify effectivness.
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Old 08-27-2010, 01:54 PM   #25
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Quote:
Originally Posted by mbtech View Post
When I worked at Garrett we had many engineers that came from auto manufacturers, most told me the break in most used (in a vehicle) is:
Start vehicle
warm up at 1500-2000 RPM
after oil temperature reached operating temp (about 10 mins after water) shut down
check all fittings connections make sure everything is stout.
after engine cools down about an hour start engine wait for oil temp to reach operating temperature again.
Drive vehicle slowly make sure you have all gears and oil pressure is 100%, and temperatures are good.
Now the break in
Maintain 20-25mph in second gear. Slowly open up throttle to 50% until 55mph is achived(or about 5000rpm)
then let off throttle. (still in second gear)
Let engine braking slow vehicle back down to 20 mph. Repeat 4 times.
Now open up to 75% and 5000 rpm and once again engine brake down to 20mph.(4 times)
Now open throttle to 100% and up until 6000rpm.engine brake once again down to 20 perform this about 6 times.
(some transmission with very short gearing may perform this cycle in third gear)

I have been told after this cycle engine is almost broken in. (depends on ring material) I have run this cycle many times. Works good but I never had any intramentation installed to verify effectivness.
I'll second this as a good controlled method for engine break in.
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