<VV> Engine Problem

[Andy Clark]

Does it behave again if you reduce the speed (or RPM)?
Andy Clark
1966 140/4 Monza Sedan
1966 140/4 Yenko Clone
1966 180/4 Cord 8/10 #60
----- Original Message ----- 
From: "Smitty Smith"
Sent: Sunday, July 02, 2006 7:53 PM
Subject: <VV> Engine Problem


>
> Smitty Says:  Ok guys here is another one for you.  (Why do I get all the
nutty ones)   Engine has always been quiet and runs strong.  Now at a little
over 100K miles.  On the highway at 80 degrees and 60-70 mph it starts
missing and backfiring.  Mostly out the tailpipe.  Very ratty and ragged as
one would run with bad plugs under full acceleration.  But only when HOT.
Engine shows no signs of overheating.  It has received new plugs, wires,
points kit (rotor,condensor etc), cap, coil, points plate and replacement
(proper) distributor.  It is not carbs.  If it is not ignition then it has
to be mechanical.
>   I have one theory, now lets hear yours.  Last "O" ring job was over 10
years ago.  I wonder if something has worn to the point that some of the
valves are just barely closing.  Thermal expansion could be causing them to
go less than fully closed when the engine is fully hot.  Like I said, lets
hear yours.
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