[alfa] follow-up on 2200 rpm rattle/10548 cams

["Watry, Andrew (LNG-SFR)" <Andrew.Watry@xxxxxxxxxxxxxx>]

I asked a couple weeks ago about the probable source of a harmonic buzz or
rattle about 2200 rpm in the 1750 in my Giulia Super.  The suggestion that
it was the upper timing chain seems to be right.  I replaced it yesterday
while putting in 10548 cams and setting valve clearances and the buzz is now
gone.  The old chain had significant droop when held "horizontal" sideways
compared to the new chain, and the pins on the master link showed about
1/32" offset at the middle and side link pieces.  So for anyone else with
this symptom, the chain might be the answer.   The buzz occurred even though
the chain was tight enough not to rub on the inside of the engine.  I can't
say how many miles or years on the chain, because this was a complete engine
I bought from APE five years ago.

After one day's driving the 10548 cams feel a tiny bet less torquey off
idle, but come in stronger all the way up from about 2000 rpm on.  Really
nice mid-range, and the engine just seems to breath a lot easier.  This is
with Webers on an otherwise stock engine, cams timed at 102 degrees and
clearances set at .018" intake and .021" exhaust. The whole project,
including several rounds of cam removal to get the clearances right and
timing the cams, took about four hours.

Andrew
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