<VV> Re: Spark Plugs

[vairologist@juno.com]

> I would like to try using modern spark plugs.  I have no more AC44FF 
> plugs left and I was wondering what the most popular plugs are.  I am 
> running a  stock ignition system on a 140.
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Smitty says:  Ron, as long as I can get them I will use Autolite 425s for
an engine that gets worked hard.  For a more gently used daily
driver/short run engine I would go higher in range to 475s.  Of course
they are of the "missing thread" variety and a thread chaser should be
used before going back to the "full thread" type.