<E30 M3>Timing chain replacement

["Thomas Maus, Jr." <tbm2@xxxxxxxxxxxxx>]

I am pushing 99 big ones on the odometer, and getting a funny rattling sound
that comes on around 41000 rpm's (and then goes away around 43000 to 450000)
which leads me to the conclusion that it is time to think about replacing
the timing chain.  I am looking for advice, information, or possibly the
location of a FAQ page covering this malady.  I will have it done by my
mechanic.  I have heard about a "lower tension(er) rail" should this also be
replaced?  Are there any other areas that should be looked at, or possible
upgrades (not underground, I'm not married) that make sense at this time.

I drive the car on the weekends, and track it about every two months,
autocross in the summer.  It has the necessary, usual upgrades; chip(JC),
cam gear, oil pan baffle, air box, yada, yada...

I would appreciate any feedback.  Is Bob Stommel part of the Bubba Boycott?
When do they get back?

TIA

Tom Maus
'89 M3
BMWCCA#125328
member "Save the Digest"

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