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OEM Initial engine break-in procedure.

OEM Initial engine break-in procedure.

OEM Initial engine break-in procedure.

(OP)
Greetings,

I would like to know the initial engine break-in procedure used by major automobile manufacturers or their suppliers.

I am intimately aware of the procedures employed by race and performance engine builders. What I am looking for is what do the big guys (Toyota, GM, Honda etc) do to break-in an engine before it leaves the factory.

Any help would be appreciated in this matter

Regards,

Bryan Carter

PS – I know what the owner's manual says...

RE: OEM Initial engine break-in procedure.

I am by no means an authority on this but in my experience I've seen that: at the engine plant, engines are fired up with a natural gas / propane fuel hood brought down on the manifold. Run time is only a few seconds (just to verify start-up). At the build plant: cars are driven off the line and frequently a lap around a test track (0.5-1.5miles), mostly to capture BSR-NVH issues.

These short start-up runs don't even come close to qualifying as a 'break-in' period. So far as I know (atleast with N.A. cars) the break-in is left to the end user. AKA- the customer.

*Without data, you're just another person with an opinion.*

Hydroformer

RE: OEM Initial engine break-in procedure.

It varies. These days most will get  a couple of minutes idling before being driven onto the wheel alignment and dyno and into the lot. The next time they are driven is for shipping, full throttle, wheels spinning.

As hydroformer says, it isn't really a break-in.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: OEM Initial engine break-in procedure.

(OP)
Thanks for the responses.

This is on par with what I expected. I had hoped for something a little more comprehensive on the part of the factory. Oh well.

Regards

RE: OEM Initial engine break-in procedure.

No.

When Rover first started to commit technical suicide by going into partnership with Honda, they sent us over some prototypes.

We phoned them up, asking what the running-in procedure was. Hasty conference at the other end of the phone, and the result was "Oh, we just let them idle for a minute before loading them up".

With the exception of scuffing the cylinder liners it's a bit hard to see what running-in really accomplishes, and I would have thought that scuffing was best accomplished at variable loads and speeds.

That being said, where I work, we run every engine on the dyno before it goes into the car. I'm not sure for how much longer we'll do that.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: OEM Initial engine break-in procedure.

idling a bit before you load the engine the first time helps to keep the pin joints from seizing.

seems like a few diesel oems do a "hot check" where they run the engines up to thermostat temp and check for leaks, odd noises, etc, then confirm/set the power output.

at least one major automotive oem in the US "cold checks" engines by motoring them and measures friction as a way of telling whether everything got put in the right holes.

RE: OEM Initial engine break-in procedure.

Interesting topic as in im the process of building a nice street 350 chev.  I have rebuilt many many engines.
Normal practice is to start engine, confirm oil pressure and rev to 2000 for 1/2 an hour to break in the camshaft and lifters. Then drive with varying load and revs.  This is what i was taught years ago.  The new engine is LPG only, so i asked around and most answered load it up straight away to seat the rings!!  

What has myself confused is, whats the difference with a factory built engine that doesnt need the cam run in, and an aftermarket cam needing to be run in????

Ken

RE: OEM Initial engine break-in procedure.

Aftermarket cams might have higher valve acceleration rates and higher spring pressures.

Regards

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RE: OEM Initial engine break-in procedure.

They *might* have a different surface finish spec'd after grinding as well.  If you do need to "wear in" a cam, then I'd expect to see that the surface is initially very "peaky" when profiled, and that bearing area increases rapidly as the peaks are worn down (just going by what some liners look like, as some have probably recognized).  


RE: OEM Initial engine break-in procedure.

I'll have to agree with Greg on the wheel spin deal.  Having worked at a couple of the Big 3 outfits and on the docks at Long Beach...One special case...a really pretty bright red Ferrari at full chat, tires smoking, haulin' a** down the dock!!!

Rod

RE: OEM Initial engine break-in procedure.

When OEM's measure profits on pennies or less per item, spending 1/2 hour on a break in dyno just doesn’t happen (on the mass production automotive side).  One of the primary reasons for a break in is to allow friction items (mostly the rings, piston skirt, and cylinders and the cam surfaces) to mate.  With today’s precision machining and rolling friction surfaces (cam followers) there is little need for a strict break in procedure.  A simple light load or fast idle the first minute or so followed by moderate driving the first hundred miles is generally sufficient.

An initial dyno and motoring dyno is performed at the OEM stage, but this generally lasts no more than a couple of minutes at most.  At a major US OEM engine assembly plant in the early 70’s, I saw a carousel dyno, where 8 engines are worked at once, run on a dry gas (this one used natural gas) while oil leaks, oil pressure, and initial run in were performed.  As each engine was completed, it was removed and another installed.

Oil leaks can be checked by vacuum/pressure drop with 5 psig air pressure, oil pressure can be checked statically too.  Originally, with manually adjustable ignition timing, that was performed at this stage, along with engine balance.

If the engine is built right and the human factor removed (the dreaded “Monday morning, and Friday afternoon” engine scenario) there is no reason the engine should be almost ready the moment it is installed.  A site visit with a major piston ring manufacturer will show the research being done to allow rings to seal almost immediately, providing the proper cylinder wall finish is provided.

As a real life example:  In the 60’s, where each engine was assembled by hand, with individual build up stations, and 60’s metallurgy, it was expected for an engine to last less than 100,000 miles, frequently with at least one valve refresher during that period.  When emission restrictions became enforceable, the engine manufacturers had to tighten up the production processes and refine the build procedures.  With today’s emission mileage warranty requirements, it is rare to see an engine ready for the scrap heap in less than 100,000 miles, with 200,000 not uncommon.  Imagine the warranty costs if an OEM had to rebuild engines routinely at 60,000 miles.  We still see smokers at less mileage than that, but a simple check of the required routine service shows that little attention has been paid.  By simple observation, it appears that one manufacturer in particular seems to have a problem with smoker engines in vehicles approaching 5 years in age (I would guess about 75,000 miles).

Franz

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RE: OEM Initial engine break-in procedure.

When I worked for a major diesel truck engine manufacturer more than 20 years ago, they dyno tested every engine.  The engine ran for about 30 seconds to bring the oil pressure up then it went to "high idle" to check the govenor setting then it went to rated power speed to verify the power rating.  Total time was under 90 seconds.

About the aftermarket cams, I suspect they are not micro finished like the better OE cams thus the need for extended breakin.  My experience with aftermarket producers is they do not have the same level of engineering, QA or production technology as OE.  I know that is a gross over-generalization and there are exceptions but the general poor quality in the aftermarket is astounding.

RE: OEM Initial engine break-in procedure.

I don't know about all that cam finishing stuff.  In my experience many of the aftermarket and performance camshafts are made on the same machines by the same mfgrs as the OE cams.  From what I have seen the finish is equal...perhaps breakin specs have more to do with product liability/warranty and convention than actual wear rate.

Rod

RE: OEM Initial engine break-in procedure.

If the OEM cam has say 0.380"lift and 60# on the seat pressure spring pressure, and the aftermarket cam has say 0.650"lift and 120# on the seat, the need for extra precaution during break seems obvious to me.

Regards

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RE: OEM Initial engine break-in procedure.

I have always been under the presumption that idling at a solid speed, IE, 2000rpm, while great for breaking in camshafts, is absolutely HORRIBLE for piston ring seal.

RE: OEM Initial engine break-in procedure.

Patprimmer,

  i think you hit the nail on the head with the higher spring pressures and more aggressive lifts!.  now what is the best way to seat the rings?  OEM dont seem to worry about this, so my guess is  modern manufacturing is precise enough that a good seal is almost instant.

Ken

RE: OEM Initial engine break-in procedure.

well, what exactly do you suppose is happening when you "seat the rings?"

RE: OEM Initial engine break-in procedure.

No scarring,scuffing and a good ring to cylinder wall relationship begins...   :)

RE: OEM Initial engine break-in procedure.

seat the rings... ?  im sure that is where all the high spots are worn down on the cylinder wall to enable a good seal.

RE: OEM Initial engine break-in procedure.

2K Rpm ? Why? Funny a nice old engine like a D342 Cat that hits rated HP at somewhere around 1300 rpms. Can't reach that supposed magical 2K cam break in rpm. And besides at that rpm the cam is only spinning at 1K. I can't see any thing special happening at 1K rpm at those lobes that doesn't happen at 5 to 600 rpms.?????

RE: OEM Initial engine break-in procedure.

Maybe theres more heat generated at a little bit higher RPM and thats helps the break in process.

RE: OEM Initial engine break-in procedure.

Maybe there is more oil flying around and lubricating the cam.

I am sure 2000 rpm is not appropriate for all engines. It is the benchmark rpm for typical American V8 car engines.

I doubt there is much demand for hotrod cams for big diesels.

It might be better to say run at 2 to 3 times standard idle with no load to break in the cam, then short bursts from idle to half maximum speed, then progressively increasing rpm for short duration full load runs with short rests between to stop localised overheating. The indicator of how long this takes will be the reduction in blow by.

It really does depend largely on many factors like compression ratio, ring materials, ring dimensions, bore accuracy, bore surface finish, bore material, bore stability, piston speed, cylinder pressure, piston to bore clearance, ring grove clearance etc etc

Regards

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RE: OEM Initial engine break-in procedure.

Many of the big Diesels i rebuilt, mainly Cummins, have roller lifters. rolling is certainly easier than sliding friction. Alot less chance of Galling.

Pat, i agree with your comment on having more oil flying around at higher than idle RPM.

Ken

RE: OEM Initial engine break-in procedure.

I don't think I've ever done a cam break-in at a constant rpm.  Varied, between ~2000 and 2500 or so.  It's been explained to me in terms of varying the oil spray patterns that you do not want to maintain a steady rpm.

My offhand thoughts behind why 2000 or a little higher is used for performance cams is to reduce the loading as the follower goes over the nose.  You get to use the cam's negative acceleration to your benefit this time - instead of worrying about floating the rest of the valvetrain clear of all contact with the cam you're using a very mild case of this to overcome just a portion of the spring load.  Valve train inertia will use up more of the spring force at any given position if you let the cam profile accelerate linearly out from under the follower faster, and more rpm helps this.  Perhaps 2000 rpm or so provides a good balance between decreased loads over the nose and increased loads on the opening flank.  And/or maybe it represents a good compromise between minimizing camshaft lobe wear and wear elsewhere within the engine (bearings, rings, journals, etc.).

If I'm not mistaken, the recommendation for breaking in double and triple spring cams is to use only one of the springs; obviously another means of reducing loads over the nose.

Norm

RE: OEM Initial engine break-in procedure.

SAE has published many papers on engine break-in, although the actual OEM procedures may be semi-proprietary.  Here is a current reference:

2004-01-2917 (SP-1894) "Effect of Break-In and Operating Conditions on Piston Ring and Cylinder Bore Wear in Spark-Ignition Engines"

RE: OEM Initial engine break-in procedure.

The old Cat D342, D353 etc. All had flat tappets. (Non Roller) At break in the engine is idled for the typical 5 or so minute warm up period till a load is applied.

RE: OEM Initial engine break-in procedure.

im sure that is where all the high spots are worn down on the cylinder wall to enable a good seal.

What, no changes at the ring/groove interfaces?  

Did you mean sealing gas in, or oil out, or both?  Do the peaks on a plateau-honed cylinder liner really have any lasting effect on sealing? Does the answer depend on what you meant by "sealing?"   Is gas-sealing so detrimentally affected by the presence of "initial peaks" on the liner that a customer would notice any sort of performance degradation while waiting for them to wear off?



 


RE: OEM Initial engine break-in procedure.

Well, here's a puzzle.

As demonstrated above I'm a bit of an agnostic when it comes to running in, but, I am frequently told that the fuel consumption in cars improves rapidly over the first few thousand kilometres.

So, what's wearing in? Maybe it's the trans or the diff?

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: OEM Initial engine break-in procedure.

Maybe ring tension relaxes a bit, maybe piston skirt clearance opens up a bit as the very tips of the high spots on the bore are worn, and as the pistons wear a bit.

Ring tension can be reduced by the rings taking set in the compressed position, wear in the bore, wear in the rings and wear in the ring groves.

Gear boxes and final drive gears probably contribute more in my opinion, especially crown wheel and pinion.

On my engines, the blow by reduces considerably within a minute or so of power runs.

Regards

eng-tips, by professional engineers for professional engineers
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RE: OEM Initial engine break-in procedure.

On my engines, the blow by reduces considerably within a minute or so of power runs.

For blow by to reduce, something must change somwhere, and the ring/cylinder wall seal and to a minor extent ring/ring groove is it.
 I would say its a form of lapping, so the parts mate together to live a long and happy life!

Ken

RE: OEM Initial engine break-in procedure.

Well, I get to take a practical look at this ring thing next week...new rings and bearings for old Rusty Booger...for the Laguna Seca race in Oct.  I'll take a leak down after assembly, after initial warm up and, after the dyno runs.  I'll post them here later, maybe in a couple weeks.

Rod

RE: OEM Initial engine break-in procedure.

the fuel consumption in cars improves rapidly over the first few thousand kilometres

Are you sure that reductions in mechanical friction are to blame (if you halved mechanical friction, what fuel econ benefit would you expect to see)?  Could the performance of the fuel injectors, or some other part of the combustion system, be changing as well?

All of the "soft" bearings within the engine will change shape slightly during this initial period, and the bearing clearances will increase (some more than others) - this may account for a fraction of the friction reduction (hydrodynamic rather than mechanical).

blow by reduces considerably within a minute or so of power runs

By blow-by, do you mean the flow rate of all gases from the crankcase, or just the visible portion (many people refer only to the visible portion)?

When you say power runs, are you refering to only the initial few minutes that the engine runs near full power output, or every subsequent run at high power as well?  Blow-by should drop temporarily every time the engine returns from high power to a lower setting, due to gap shrinkage (ring thermal expansion relative to bore) and piston clearance reduction (piston expansion).  It should "grow back" as the piston and rings cool.  Is this consistent with what you've observed, or are you talking about a permanant change?

Ring tension can be reduced by:
1) rings taking set in the compressed position people often refer to this happening, but at Tmax<250degC I can't see much tempering happening in steel rings.  I've also never noticed a significant change in tension between new and slightly-used rings.  
2) wear in the bore yes, this does happen, but in a 100mm bore you'd need ~0.75mm of wear (diametral) to give you a ~5% change in ring tension - so I'm guessing this effect is pretty slight
3) wear in the rings ignoring the change in cross-section, you'd again need about 0.75mm of wear to get 5% change in tension (with that much wear, you couldn't ignore the change in x-sec, but the real initial wear is more like 0.005mm and is limited to a portion of the ring face)
wear in the ring grooves Sorry, I have no idea whatsoever how groove wear can affect ring fitted tension.  Wouldn't the ring fitted tension be the same even if the piston was entirely absent, and the ring was just sitting (properly oriented) by itself in the bore?


I'll take a leak down after assembly, after initial warm up and, after the dyno runs.  I'll post them here later, maybe in a couple weeks.  Do you lube the rings or bore during assembly (might make a big difference in the results)?  I know that many people "clock" the rings in the bore when they're building an engine, believing that this reduces blow-by.  I would agree that this may slightly improve sealing on initial startup, but after that the ring gaps go wherever they please, negating the effect.  Anyone have any comments on that?  Is clocking the gaps important for initial startup, because compression would otherwise be too low?  Is the lack of a somewhat-evenly-spread oil film on the cylinder wall the missing ingredient for initial compression?






  

RE: OEM Initial engine break-in procedure.

I am talking about visible blow by and a permanent effect.

In my observations, the rings fit closer to the piston, or hang further out of the groves with the piston removed after the engine has done a few passes. The rings are easier to compress and refit to the bores as well on a slightly used engine.

Re grove wear vs tension. OK I was grasping at straws there.

No matter what the reason, engines do turn easier by hand after they have been run.

Regards

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RE: OEM Initial engine break-in procedure.

Is the effect you observe only on the first power run, or does the blow-by progressively decline with each subsequent power run, until you no longer have visible blow-by?  

...Or is it the case that after every power run, you have a certain amount of visible mixture coming from the crankcase, and as the engine continues to run and cool the visible fraction declines, but then at the end of the next power run the cycle repeats?  

I would also note that visible blow-by may not be a useful indicator of "ring seal" at all, since it doesn't necessarily correlate to the amount of gas passing the rings.  In some select situations the two can be related (if, for example, the concentration and size distribution of oil droplets in the crankcase were relatively constant, and breather performance was not influenced by total blow-by volume, and piston temperature was constant, and cooling jet flow was constant, then I would expect that more gas flow means more visible stuff, and vice-versa.  In other cases, more gas flow means less opportunity for droplets to clump together into a visible size.  It can also happen that visible CCV constituents are most closely related to piston temperature and cooling jet flow, with next-to-no relationship to blow-by gas flow.  Changing ring-groove clearances, perhaps due to wear, can also affect the size of droplets in the blow-by stream, making them more or less visible, without having a big effect on total gas flow, as can carbon and "gunk" accumulation at key locations on the pistons).  

In any case, it has been my experience that blow-by (total, measured with a flow meter in a big duct) and oil consumption of an engine vary somewhat during the first 50 hours of running (or so), then tend to level out for a while, before heading off in whatever direction they eventually drift in (usually for the worse).  There is usually an initial period of "rapid" change (although the magnitude of the change is generally pretty small compared to the magnitude of the parameters in question - 10% or less), after which changes happen at a much slower rate.  Running at higher cylinder pressures would tend to make the "rapid change" period shorter, by a bit, than it would be if lighter load was used.  There is a measurable change in bore surface finish, and the peaks do get smoother.  The tops of the "plateaus" become more like plateaus and less like pincushions.  I doubt that gas flow past the ring faces changes much as a result of these bore surface finish changes - the peaks aren't THAT big, and they should be pretty "mooshy" when the gas-loaded ring rubs across them.  The ring and groove flanks both become smoother during this period as well, and regions where loads are concentrated tend to get "rubbed down" a bit - I would tend to attribute gas sealing improvements to better ring-groove contact and reduced groove runout.  Then there's the accumulation of oil in the inter-ring volumes and in the backs of the grooves, which also likely helps to reduce gas flow past the rings.  

RE: OEM Initial engine break-in procedure.

It progressively improves over the first few runs. The runs increase in duration and RPM from say 3 seconds at full load at med RPM to a final full power run for 8 or 10 seconds. The level of improvement tapers off until improvements are not detectable by eye. The RPM level and duration are increased according to the amount of blow by noticed. The engine is slowed to a no load fast idle for a minute or so between runs

My method is purely subjective using the only tools I have for this, which are my eyes.

I have no means to measure cylinder pressures, nor internal temperatures. I do monitor oil and coolant temperatures to make sure they are "normal" but normal probably covers 85 to 110 deg C.
for coolant and 90 to 120 deg C for oil.

Regards

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RE: OEM Initial engine break-in procedure.

Isaac, I think your 'overthinking' the problem.  It's pretty straightforward from a practical point of view.  If all the demensions are in spec, ie, no bore distortion/taper and proper piston specs then, no it probably makes little difference in the long run wheather you 'clock' the rings on installation or not.  That is not to say I don't do it, rather mechanically, out of habit.   My ring gaps are ~0.014" cold and, again, no I have not done a leak down on a cylinder with gaps alligned (to be honest, I probably won't either) Anyway, it'll have enough compression to start as static is 14:1 on the Mini and 15:1 on the Lotus.
At one time in my life I succombed to the 'drag racer mentality' and pushed the pistons in dry or on one particular 394 Hemi, used a fine 'jewelers rouge'...not these days.  Now I liberally oil the cylinder AND the piston/rings before assembly. The new piston never runs on a dry cylinder and I have seen no unusual anything in the last twenty or thirty engines save a broken ring on a street Ford Fiesta 15 years ago.
[Another, sorta related question to explore...Why do I still run my engines in on paraffin based lube instead of just going to synthetic to start?  The OEM's that use syn don't bother?]

Quote:

"wear in the ring grooves Sorry, I have no idea whatsoever how groove wear can affect ring fitted tension.  Wouldn't the ring fitted tension be the same even if the piston was entirely absent, and the ring was just sitting (properly oriented) by itself in the bore?"

Firstly (or lastly), ring tension is ring tension until the fire is lit...then, especially on Dykes or drilled pistons, the tension increases, a lot.
Secondly(or firstly) from my experience, when the ring groves begin to exceed a certain wear limit, expecially the top ring, blowby increases dramatically.  I see it as a result of "ring flutter" whereby the ring no longer makes a square, perpendicular fit to the cyl.  I  come by this opinion from some tests I was privy to on some 'dykes ringed' versus 1/16" versus 1mm versus zero gap top ringed Cosworth pistons in a Lotus Twincam 1594cc engine many years ago (sorry, I don't recall the specifics of each type. I do recall that the Dykes and 1mm were about the same.)  I have a set of JE's with 1mm's (for that 10,000rpm "one of these days" engine) and a set of Venolia's with Deves 1/16" for the vintage engine (run in quickly and last a long time). One BIG difference in ring type is overall bore clearance...the smaller the ring the more critical the fit.

Sorry this post got a little longer than I had intended.

Rod

RE: OEM Initial engine break-in procedure.

Well, it had to happen one day. Rod is Wrong, or at least, not  completely accurate. We still use running-in oil for our first fill, in production, and pay more for it than the normal stuff.

But, I think it might be a bit special since our darling customers tend to skip or delay the first (1000 mile) service, so it has to stand up to regular use as well.

Cheers

Greg Locock

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RE: OEM Initial engine break-in procedure.

especially on Dykes or drilled pistons, the tension increases, a lot.  ... sure, but I'd call that radial pressure, not ring tension.  That's what I was referring to when I mentioned "gas-loaded" rings.

RE: OEM Initial engine break-in procedure.

Awww, shucks.  I was on a 65 year run, too.----- Oh, wait!  The way I read it, Greg...since I still use Castrol to run in my engines and then switch to Mobil 1...doesn't that mean RIR?

Rod

RE: OEM Initial engine break-in procedure.

Your correct, Isaac.  I should have said that in relation to ring tension, radial pressure remains the same until the fire is lit, etc.  My tongue was over my eye tooth and I couldn't see what I was typing. I knew what I ment.

Rod

RE: OEM Initial engine break-in procedure.

Oh, I was commenting on "The OEM's that use syn don't bother?" but I missed the question mark. Damn, so that's 65 years of an unblemished (yeah I bet) record.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: OEM Initial engine break-in procedure.

Speaking of break-in oil:
when I had responsibility for engine tear-downs at Chrysler engine development, we often disassembled new production engines to use as bases for test engine build-ups.
Zer-mile engines that had only seen the engine plant hot-test run of 30 seconds or so.

I was horrified to see the amount of swarf that was left in the oilpan - a mixture of metal shavings, core sand, and just plain dirt.
Since that time I have immediately changed the oil and filter upon getting home with any new car, truck or motorcycle.
-----------
And on a related note,  I have observed that vehicles that had been used extensively for passby noise testing had much lower oil consumption than one might have expected.  I attribute this to the brief high-rpm/light-load operation they saw in the noise tests.

RE: OEM Initial engine break-in procedure.

OK...the engine went together faster than I had expected and I only bolted up the flywheel/clutch (minus the clutch plate ONE time...dumb, dumb, dumb (seems like I could learn this sh**).
Leak down after about a minute of turnover on the starter motor, sans sparkplugs, (oil pressure was 35psi) gave about 15%.
Leak down after a couple minutes to set ign. timing then about 15 minutes of high idle > 2000 rpm (oil press 95 psi) to warm up stuff (set valve lash warm) and  another 5 minutes of 1500 to 6000 full throttle "pops" then to a low idle (barely) for a minute and shutdown...< 5% !  This indicates that, along with the  fact torque to turn it over (sans plugs) is 10 ft/lb to break and <5 ft/lb to keep it rotating !!!!!!!
Man, I'm hoping for good things here. Leak down should drop to <3% and cranking pressure will probably still be in the mid 260 psi range, even with the 310 cam (CR is 13.87:1).
Can't get dyno time until next week (short notice, I did not think I could get this much done this soon)...nothing a handfull of Excedrin extra strength won't cure.

Rod

RE: OEM Initial engine break-in procedure.

OK...I finished the dyno runs yesterday and checked the compression and leak down.  The compression ck was a little up and down (????) as it's usually even across the board...this time, with about two hours and three pulls on the dyno and the bigger cam, it's 225-240-235-230 after 8 turns and, later the leak down was barely readable on my guage...something less than 3% on all four cylinders.  Also I picked up 13.25 hp and 4.86 ft/lb of torque extending the rpm range by 300 and not loosing anything below 5000 (the engine never sees any use below 5000 if I do my job right).  I'll do further tests, of course, after the Laguna Seca race in Oct.

Soooo---it sure did not take long to run in, did it?
Oh yeah, I changed the oil from Castrol 20W-50 to Mobil 1 after the dyno runs. Surprising how much stuff comes out in such a short time even though I treat engine building like surgery!

Rod

RE: OEM Initial engine break-in procedure.

While working as an intern at the buick plant 2 decades ago the routine involved sending the long block through a station where a booted manifold was servod against the heads and exh manifolds were pressed against the exh ports.  
The starter was engaged (sparks flying) and baby takes first breath.  Run time was under 2 minutes and involved a prelube run up.  I think there was some sort trash rinse before the pan was installed but a lot of small metal trash, manufacturing residues, core sand and misc FOD.  I visited a northstar plant recently and it was clean enough to eat off the floor let alone the engine assembly.

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Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
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Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

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