breaking in - what do i have to look up for ?

Jordo!

1. I did my first change at the recommended 6000 K or so. Some people like to do one immediately after break-in period, but I don't feel this is necessary.

2. Personally, I like Castrol syntec 0W-30, but there's no clear evidence that any one oil is better or worse than another. Many people on here seem to like Redline. Whatever you choose to use, synthetic is probably a better choice than regular oil, but so long as you do regular changes, any certified oil should be fine.

3. Only if you intend to track it. There are several threads on this -- search.

4. I recommend trying to avoid maintaining constant speeds for first 2000 K or so, and allowing the engine to coast down from various RPM's. Likewise, I advise against redlining it until after the break in too (this is essentially what Nissan reccomends, BTW. I've done this for more than one new motor, and no issues). However, different people have different theories on optimal break-in. This too has been discussed at length -- search.

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