To the mechanical Gurus on the forum - Do you agree or disagree with the following post by Lance Wolrab. If you disagree, why.......

"This is from a post to another list originally made 9/16/1999. I have
been using this procedure for many years (at least 18 years). I both
agree and disagree with the link you posted. I'll explain why after
you see my procedure.

I have a standard break in procedure that I use, it takes about an
hour if you are diligent, and when you are done, break in is complete.
The biggest point of grief with a new engine is the unrelieved
stresses in the pistons. You want to heat and cool them in a
predictable way with an incrementally increasing thermal load. I
usually start at 20% throttle and go in 10 or 15% increments until I
get full throttle. Bursts should be 15 to 30 seconds, followed by 5
minutes part throttle cruise to let the pistons cool and resize
themselves. You can figure out that 30 seconds in top gear at full
throttle will have you going pretty fast down the road, so you need a
clear stretch to do this, but I have never had a problem with leak
down or bad piston fit using this technique. That crap about "XXX"
miles is just so the average driver doesn't blow things up.

Also, I assemble the cylinders dry, but turn the engine over for about
15 seconds with no fuel or ignition before my initial start up, then I
run it up to about 25% of redline as soon as it catches for 30 seconds
or so. Once I have my initial 30 seconds and no gushing leaks, I take
it out for a drive right away. I want to put pressure on the rings and
valves to get them to seat well and that can't be done without a load,
so off we go down the road for about 5 minutes, then return to the
shop to check for oil or coolant leaks. If all is OK, back out on the
road for final break in.

OK, that's what I have recommended. I disagree with Motoman because he
is ignoring the whole issue of grain structure in the pistons. If you
are using used pistons, then there is no need for any kind of loading
tactics like these, just a few full throttle runs at soon as the oil
is up to temperature to seat the rings and you are done. Cast pistons
have not aligned their grain structure after casting, and forged
pistons have unrelieved stresses from the forging process. Both
require heating and cooling cycles to allow the grains the opportunity
to align themselves under thermal load. It isn't possible to do this
in the manufacturing process because pistons are not heated evenly in
service. This process is no different than heat cycling your tires, a
well known science among racers. I completely agree with Motoman's
assessment of the manufacturer's recommendations. They are crap. I
also completely agree with getting a load on the engine as soon as you
can. I didn't notice any admonishments about allowing a new engine to
idle, but I NEVER allow a fresh engine to idle, it is the kiss of
death IMO.

Ken, in your situation, you have little or no control over how the
engine was initially fired, and BMW being reasonably intelligent and
diligent have already used an initial firing procedure designed to
seat the valves and rings quickly. Just take it out and drive it, put
a load on it, and be happy with it.

Lance Wolrab

 

I certainly disagree with installing the pistons and dry. Engine breakin, after 35 years of engine building experience, is simple and short, but it is also a continuous process for the life of the car. I have posted what I do several times and it makes for a tight engine that burns no oil.

1. Always bring engine to FULL operating temperature before high revs.
2. Drive the car easy for the first 10 miles or so, varying the rpm's from 2,000 - 5,000.
3. Then, start bringing the engine up to maximum rpm's and letting the engine bring the revs back down by coasting in gear.
4. Repeat several times in order to create maximum heat in the cylinders.
5. Drive around at lower RPM's for several more miles, remembering to vary the speed of the engine every couple of miles.
6. Repeat number 3, 4 and 5.
7. Park car and let the engine cool down overnight.
8. Repeat all the above 2 more times.

Your engine is now fully broken in correctly and can be driven hard from here on.

Periodically, hard engine braking is necessary to get the cylinders as hot as possible and forcing the rings against the walls for maintaining proper wall smothness.

Every builder has their own specific method of breakin, and you can go back and forth forever in this debate, but it is not a complicated topic. Porsche suggests that the engines need to make about 6 million revolutions before it is broken in, and I maintain that after only a hundred thousand or less revolutions, what is going to break or break in, has already done so.

 

It's always amazed me how many builders have their own methods. I know many people that build motors and they all have their own methods, and most will say anothers methods are wrong. I think the post above is pretty dead on.

 

The second break in is very close to what I follow, but I generally do it for a little more mileage. The mileage for a couple of reasons, it gives the rings a little more time to seat properly, and because most customers will not be as diligent or procedural as needed. I'm guessing the rep. that I talk to at Wiseco says 3000 miles just to cover their ***. But basically he talked about the heat cycling necessity.

Not to mention, the changing of oil and filter, many times after startup, and during break in.

"Letting the engine bring the revs back down", otherwise known as vacuum pulls, is key if you ask me. Any time your accelerating, there is a decent amount of load on the rings. And if your are a little spirited about it, even more so. But in general, the rings do not get that much pressure in the opposite direction in normal driving, without doing the vacuum pulls..

I have compared my compression #'s to my employees(my tuner), nearly Identical motor build, but he does the beat on it right away theory on his personal cars. Although not scientific, and maybe there are other unknown factors, but my compression #'s have been much better right away, and down the road.

 

*Resurrected!*

I've ordered my new 2010 STi and saw 1999Porsche911's advice on breaking in the new engine and I have to agree with him for the entire process. I had heard of MotoMan's advice and I've known people break it in that way and haven't had any problems, but I like the way it's worded by 1999Porsche911.

My question/debate is at what point do I finally switch over to fully syn from the dino oil? Any help on this would be great.


Edit: The reason why I didn't send him a PM is because I thought this might be useful for anyone else hopping around the web wanting to properly break in their new ride. Thanks!

 

I have nothing to base this on, but I generally switch to synthetic after 5k on a new motor.

 

I was thinking at about the 2000 mile mark. But I'm tempted to do it sooner.