That one is problematic -- the single row chain is VERY weak in
comparison to a dual row one, and should really be changed to a dual
row chain if the single one is still there. Many were swapped early
on, though.
The other "gotcha" is that the block was just drilled and tapped for
the head bolts, and they very often simply remove the threads when the
heads are removed. Special inserts must be used to repair it (they are
put in at the factory on all later engines), and a special jig is
required as they don't go in at a right angle to the block face. About
$1500 last time I know anyone checked.
Otherwise it's identical to a 420 for all intents and purposes. It IS
a hyper-ectotic (or whatever) silicone/aluminum block, meaning the
cylinder bores must be etched if you have to bore it out to remove the
aluminum from the precipitated silicon. Only a problem if severely
overheated or run out of oil, otherwise the bores are pristine, no
matter what condition the heads are in.
Peter
