<VV> Advanced Timing

[GARY READORE]

I have a 65 Monza convertible with powerglide that does something odd. 
4-5 months after setting the timing (to about 14 degrees BTDC) the timing
becomes advanced and the car starts pinging (clattering).  I reset the
timing and each time after about 4-5 months it starts clattering
again.  When I check the timing it is advanced again.  The distributor
hold down bolt is always still tight when I go to reset the timing so
that doesn't appear to be the problem.  Does anyone know why it does this
or what could be causing the timing to keep advancing?.  The car
continues to run strong/well with no problems.  FYI., I drive the car
quite a bit (especially in the non-Summer months) and put about 7,000
miles a year on it. Thanks!   --- GARY READORE--- gary62@ix.netcom.com---
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