Oil changes with rebuilt engine

[Hugh Barnes]

comparing the cost of *relatively* cheap multigrade and regular oil changes against the cost of a new engine, regular and often seems a no brainer. With the new engine in the Cabriolet last year, I did the first change after 20 miles, the second after 50 and then the third after 100. Never crossed my mind to be more frugal. And the oil changes seemed to be worthwhile in the way the oil came out of even clean as a whistle newly built engine...

[Ian Williams]

I am another a strong advocate of not nursing an engine and disposing of oil very frequently during break in, examine what is in the oil after just 50 miles Howard and make your own choice.

[Chris KC]

I neglected to mention that I run a pressure fed engine with a full flow oil filter, thus I don't worry too much about sizeable debris ending up in my big ends. Splash feeders and gauze-strainers may rightly be more cautious. Even so, I wouldn't tip away oil which is still 'golden'.

[Bob Culver]

ACL, the major manufacturers of rings in Australasia, and who probably provided the new car industry when it existed, recommend for conventional cars that the first oil change be "as soon as possible and certainly before 500km". Presumably the iron dust, honing remnants, and workshop dust, grinder spray etc finds its way through the filter sooner or later.
(Incidentally hard drives contain very powerful flat magnets.)
From what I have read it seems a thermostat would likely have more effect on cyl wear than the difference between cheap and expensive oil or frequent changes