Controversial topic: how to properly brake-in new engine?

[sayemthree]

[nusevad]

I took my car up to 5,500K RPMs a few times...not every time i drive but on occasion. Its hard to resist not too..

[mkoesel]

I'd love to see one of the big car mags/shows (maybe TopGear - they seem to be well funded) do a wide battery of tests on this topic.

[e36jakeo]

Skip Barber uses a bunch of Porsche 911s at Laguna Seca for the Skip Barber driving school. I was told that, to test out whether break in made made a difference, at the beginning of the season they broke in half of their new 911s as per the manufacturers recs, and the other half they just drove them like they stole them right from mile 0. At the end of the season they broke down the engines to see if there was a difference.

There was none.

There is something to say about somewhat of a hard break in. I will probably drive the car hard and variable, but below about 6000 rpm, for the first 1200 miles.

[Hans Delbruck]

Originally Posted by FifthStreetz

o god, not that motoman crap again...

Yeah, no kidding! That "break in secrets" link has been circulating the car forums for several years, always causing debate!

Seriously, it's a good idea to follow the factory procedure if you want to fully protect your warranty. ECU's record EVERYTHING. If your engine grenades there is no doubt the dealer can plug in and find out what you've been doing.

I say this because a friend of mine with an Exige S went in for his "post break-in" service.... the Lotus dealer was able to download a sheetload of information about the car's use, and even handed him a printout. Things like: How much time was spent in various rpm ranges, the engine temperatures at those rpm, (i.e. did you hit the rev limiter? on a cold engine?) how many times the car was launched (i'm serious, the ecu can detect a clutch dump) how much time the car spent at low throttle, part throttle, full throttle... etc etc etc.

It's in your best interest to follow BMW's recommended procedure. Keep it in the recommended rpm ranges, don't full throttle it (ehhm too much), and warm it up before playing! You can break in an engine well without banging the rev limiter. You just need to make sure it experiences a variety of rpm's and conditions. And that.... is my big fat loud-mouthed opinion!

[Hans Delbruck]

Originally Posted by e36jakeo

Skip Barber uses a bunch of Porsche 911s at Laguna Seca for the Skip Barber driving school. I was told that, to test out whether break in made made a difference, at the beginning of the season they broke in half of their new 911s as per the manufacturers recs, and the other half they just drove them like they stole them right from mile 0. At the end of the season they broke down the engines to see if there was a difference.

There was none.

That is very interesting, thank you! Do you know what was involved in the engine break-down?

[swamp2]

Originally Posted by jm1234

swamp2/dangoma,

I searched for the link provided by the OP and all variants of it I could think of and the search engine can't find the other threads. If you could provide a link to these other threads that would be helpful and maybe people wishing to discuss this would post in the original thread and then this one would die and everyone can be happy?

Try google for searching m3post.com (or any site) it is almost always better than the search on the site itself. Try this syntax then check out a few of the top hits. .

[e36jakeo]

Originally Posted by Hans Delbruck

That is very interesting, thank you! Do you know what was involved in the engine break-down?

I believe they looked at the pistons and ring gear(?).

[swamp2]

Originally Posted by PencilGeek

There's an old axiom in the racing industry as it relates to street cars: "break them in hard, and they will always drive hard; break them in soft, and they will always drive like they are constipated." I noticed this with many of my own cars -- noticing that my friend's identical cars seem like dogs compared to mine (I broke them in hard).

When I was having my car dyno'd this weekend, without any prompting the guy just happen to bring up this same subject all by himself. He said it's just as true today as it was 25 years ago when we were all competing against each other in the aftermarket parts business.

Anyways, just take that FWIW...which isn't much...

I really don't get the logic. If we all agree that the motor has already been pretty much broken in at the factory due to both incredible manufacturing tolerances and finishes and run to redline (I have read this is absolutely the case with Maserati break in, i.e. Ferrari engines) what is the point of obsessing about the post factory ENGINE break in? Like I posted previously it seems clear that factory recommended procedures are more for the trans, clutch, diff, axles and even brakes than for the engine. I know with my baby I will be following the factory procedure fairly close but certainly won't obsess about a few small deviations here or there, increasing closer to the 1200 mi point.

[Mickb]

Guys

I would have thought the e92 is much more enjoyable even adhering to break in guidelines, say compared with the e46, becuase the torque peak is much lower. I mean from 3900 you still have 1100-1600 rpms to play with compared with the e46 where peak torque was only coming on stream at 4900. Perhaps some owners could chime in here on low down drivability. Also, how is the car geared (let's you you shift from 2nd at 5000 rpm, what sort of rpm are you dropped into in 3rd?)

Mick

[a burrito]

i read that before.. i think its more for motorcycle engines isnt it?

[Gearhead999s]

Originally Posted by Mickb

Guys

I would have thought the e92 is much more enjoyable even adhering to break in guidelines, say compared with the e46, becuase the torque peak is much lower. I mean from 3900 you still have 1100-1600 rpms to play with compared with the e46 where peak torque was only coming on stream at 4900. Perhaps some owners could chime in here on low down drivability. Also, how is the car geared (let's you you shift from 2nd at 5000 rpm, what sort of rpm are you dropped into in 3rd?)

Mick

It does not come alive till 5500.If you you only run it to 5500 you are missing one the most captivating experiances of this car.As long as its full warmed up it will not hurt it.My unmodified cars that have been broken in hard have allways been quicker than my friends cars that have followed the owners manual breakin schedule.

[Gearhead999s]

Originally Posted by a burrito

i read that before.. i think its more for motorcycle engines isnt it?

They are still a 4 stroke engine,so it is totaly relevant to our engines.

[Hans Delbruck]

Variances in an engine's HP could just as much be due to different build tolerances within the engine. Some engines are just stronger than others right out of the factory. So proving that the break-in was what made the engine stronger is going to be very hard to do.

If you want to keep your warranty, follow the break-in.

[m3larson]

I was easy on mine. Never went over 105MPH however once in a while went over 5500RPM when the engine was warmed up. My car still works fine..

[jm1234]

Originally Posted by swamp2

Try google for searching m3post.com (or any site) it is almost always better than the search on the site itself. Try this syntax then check out a few of the top hits. .

Thanks!

Other threads mentioning this guys site:

http://www.m3post.com/forums/showthread.php?p=2308130
http://www.m3post.com/forums/showthread.php?t=131576
http://www.m3post.com/forums/showthread.php?t=129626

[sayemthree]

just drive it at redline - 8400 rpm for the first 1200 miles!!!

[gblansten]

If you don't brake you might break.