So I did a little more digging,
and it's all about ring seating.
here's the link:
http://www.mototuneusa.com/break_in_secrets.htm
The gist is that you want to keep high cylinder pressures, NOT necessarily that
you have to flog the motor mercilessly.
Airplane engines seem to want the same treatment:
http://www.lycoming.textron.com/main.jsp?bodyPage=/support/publications/keyReprints/operation/engineBreakIn.html
http://www.cessna.org/benefits/articles/breakin.html
and I've done basically the same thing on the last 2 motors I've rebuilt, with
some success. Warmed it up, then taken it up 99 late in the evening,
accelerating to 60 in 3rd with heavy throttle, (maybe 4500 rpm) then letting it
drop to 40 by taking my foot OFF the gas, and repeating ad nauseum. Or at
least 20 times.
Having said that, if a professional's rebuilt the engine, BY ALL MEANS follow
her or his instructions.
As for cam break- in, the cams I have used have explicit instructions to avoid
idling, saying "Keep RPMs above 2000 for the first half- hour."
This DOESN'T mean that you HAVE to run 2000, just that low rpms will be
harmful. So if you run several load cycles, just don't let the thing idle.
Again, following the instructions for the specific cam is, as they say,
'priceless'
Just my '02,
Toby
> The 'theory' of which was written about is a disputed one.
>
> The grinder of the cam I used, Malvern Racing, which built a lot of motors
> for the Datsun community, disputed the 'run it hard approach'.
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