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From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Breaking in a new engine..
Date: Sat, 15 Apr 2006 01:59:02 -0400
Message-ID: <>

On Fri, 14 Apr 2006 05:35:28 -0400, "RCE" <> wrote:

>Here's some food for thought ....

He is absolutely right.  I discovered this method back in high school
oh so many years ago when for a science fair project, I built an
engine dyno and investigated a couple of interesting aspects of
2-stroke tuning.  Of necessity, I had to go through several cylinders
and pistons.  Not wanting to spend the time on "normal" break-in and
knowing that the operating life of each set would be short, I "ran 'er
hard and put 'er up wet" from the very first cranking.

Then I noticed a funny thing.  The pistons and rings run like this
ended up looking a LOT better than the ones out of my racing engines -
even after long full throttle runs on the dyno, much longer runs with
much poorer cooling than a track engine would ever see.  A light came

For a 4-stroke engine just off the engine stand, I don't even crank
for oil pressure.  I push the vehicle out of the shop, tie in an
external oiler to produce the first oil pressure, crank it up and when
I get the first indication of oil pressure from the pump, nail the
throttle.  Not for long until the oil warms up, just a few seconds,
enough to leave some nice black streaks. :-)  That puts pressure
behind the rings during the very first running when the cylinder wall
ridges are still the sharpest.  Then back to idle until the oil warms.

This initial high power run is also vital for cam break-in.  Idling a
new cam will kill it in short order.

If it has good enough mufflers to get away with it, I'll run the car
wide open up through the gears as fast as I can get away with and then
let it coast back down.  Up and down with no idling or cruising for at
least a couple of miles.  If it's a street car, it gets to the
interstate where several miles can be quickly run up using this method
with little risk of a ticket.  If it's a race car, the engine gets
shut off until it gets to the track where it's given the same
blast-up-coast-down treatment.

His recommendation about using ordinary automotive dino oil for
break-in is also spot-on.  We want the oil to be good enough to keep
the plain bearings floating and the pistons from scuffing but we also
want it to function as a cutting fluid of sorts at the ring-cylinder
interface.  If the oil is too good - synthetic, for example - then the
break-in process will never quite complete.  I learned that one the
hard way.

After the first 1000 miles or 10 hours, I change to Mobil-1 synthetic
oil.  Why?  Because over the last 30 years or so of tuning engines,
I've seen a dramatic difference in engine life over the best dino oil,
both on the street and on the track.  Other synthetics may be equal
and some may even be better but I have the history with Mobil-1 to
know that it works.

As to his question about why mfrs recommend gentle break-in, the
answer is simple - it's the safest from an OEM's perspective.  It
takes some skill and some common sense to use the up-down method.  If
they recommend running it hard through the gears, some idiot is going
to think that means run wide-open-throttle for miles - and will then
sue when he gets caught, has a wreck or blows the engine.  It's safer
just to tell the customer to poke around for a few hundred miles.


From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Breaking in a new engine..
Date: Sat, 15 Apr 2006 02:09:06 -0400
Message-ID: <>

On Sat, 15 Apr 2006 00:07:45 GMT, "Nate"
<> wrote:

>> Several of the high performance, high RPM and high compression cars
>> commonly use more oil than normal.  I have a new, '06 model that has used
>> almost 2 liters of oil in 1700 miles and it is considered absolutely
>> normal.
>Is the oil consumption something that makes the engine better...or is it
>that BMW could not engineer a piston ring to hold oil in the crankcase with
>12:1 compression?  Me thinks it is something the engineers figured the
>owners would learn to live with.  I doubt they needed the blow by to
>lubricate something in the combustion chamber.
>Again...the fact that it is normal does not mean it makes the engine any
>better than it would be if it did not consume oil.

I strongly disagree that oil use is OK, particularly in a high
performance engine.  Oil, even in small quantities, has a horrible
effect on detonation resistance if it gets in the combustion chamber.

When a properly broken-in engine uses a significant and unchanging
amount of oil, especially if it is not accompanied by decel smoking,
almost always the cause is inadequate cylinder rigidity.  Knowing BMW
like I do, I highly suspect this to be the case here.  After owning a
635CSi, working on a lot of BMWs and tuning a few, I'm extremely
underwhelmed by the brand.  It's the German equivalent of a Ford or
Chevy, pretending to be something special.

Oil burning may be normal for that engine but it sure isn't OK.  IMO.


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