Break-in Procedure

[Estoril]

Just do the break-in procedure.

[enjoy_m3]

It's really up to your confidence on the rebuild. Did you replace the piston/rings/cams/followers? Those are the main areas requiring good break in when new.

[Obioban]

I would follow BMW's recommended break in.

[heinzboehmer]

Might not be necessary, but I would personally do it (and did when I changed my rod bearings) for the peace of mind. I wouldn't want to have to tear down the engine again just because I wasn't patient.

[jbfrancis3]

Hasn't this been debated enough in the other threads from which you are quoting data points, or wouldn't it make sense to keep that dialog going? Why fragment?

[Kdubski]

Just rebuilt a motor with 111,xxx miles. Did a head gasket and rod bearings, as well as a short list of other wear and tear items. BMW suggests not exceeding 5,500 RPM or 105MPH for 1,200 miles. Other argue that the rod bearings don't require a break-in, especially seen on unregistered track cars.

What have you guys done in the past? A 1,200 mile break-in procedure in the middle of summer is going to be a tough one!