Advice: Repair, Philosophy, and Performance

[Rob Ellis <aellis@xxxxxxxxxxxxxxxx>]

[Repair]
I'm reassembling my cyl head (after resurfacing and a valve job) and 3 of
my exhaust rocker arms have major flat spots on the pads.  The others have
noticeable wear, but not as bad (intake arms are pretty good).  A few cam
lobes are a bit worn.  Would I be a fool to replace only the 3 worn arms
(keep the other arms, rocker shafts, and the cam shaft)?  I'm trying to
save money, but I'd rather pay more now than make a mistake.

Also, noting this wear in the head, should I be concerned about wear of my
engine block?  Would I be well advised to rebuilt the block now, or wait
until when/if I have a problem?

[Philosophy]
Most of the parts I remove from my car have "BMW" and/or the date (88)
stamped on them.  If I buy OEM parts, but not from a BMW dealer(no BMW
stamp), am I devaluing my car for the future?  If I were restoring the car
20yrs from now, would OEM, yet non-BMW, parts be "good enough"?  Should
I be concerned about this now, assuming that I will keep the car for a
long time?

[Performance]
If I'm replacing my cam shaft, might it be worth paying more (about twice
as much) for a performance cam shaft?  Would one notice much difference
from the stock cam in normal driving, or only after making other mods and
under racing/track conditions?  Could this (and other major modifications)
be a bad idea knowing that I have a resurfaced cyl head and an aging
engine block?

Thanks for your help and opinions,
Rob
9/88 325i 147k

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