[alfa] re: 93 spider valve noise

["C.M. Bereznoff" <cmbereznoff@xxxxxxxxx>]

Ok Alfistis,  Thanks for all of your on, and off list,
replies.  The summary to date reduces the answers to:

    1.  "Live with it, thats the way they all are and,
nothing bad is gonna happen."
            ( My neurotic, obcessive, compulsive,
perfectionist, tendencies just can't accept this answer )
    2.  "I have the same problem and need an answer, Please
send me the  answer when you find it"
    3.  "mine is fine,,,,, quiet"
    4.   and finally, ( Thank you Russ ) reduce the
clearances.

    The reduced clearances seem the answer to me.  One email
said that he was running at  0.010 intake and 0.012 exhaust.
My hypothesis is that in the 91-94 spiders, there is a
different heat transfer differential than in earlier spiders
and as a result the change in expansion and contraction
differentials are resulting in too much valve clearance and
slap, thus noise.   ( Is the higher compression ratio, the
VVT or other emission systems in the S-4 series
contributing to the increased heat ? )

    Maybe this noise is why so many S4 series have had valve
jobs done to them.  Most replies have stated that the valve
jobs did NOT fix the problem.  One owner stated that when he
changed valve guides, it helped some.   I never heard a new
S-4 spider run so I don't know what the valves sounded like
out of the showroom, but I cannot imagine that anybody would
buy a new Alfa that sounds like a sewing machine !

    Now the next questions for all of you mechanical types.

What are the risks of clearances much lower than spec ?

Are their any known benefits in performance to the much
reduced clearances ?

Is there any change in the lift with reduced clearances ?

This list has always been an invaluable resource for me and
a tremendous service to the community.
Thanks to all of you who have been helpful in the past and
the future,
and thank you Richard Welty for your work as the moderator.

Craig M. Bereznoff
cmbereznoff@domain.elided
Longmont, Colorado
1993 Spider
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