Fred Langley wrote:
> One of the reasons for resistive spark plug wires is to increase the
> duration of a spark by inserting a resistance in the circuit lowering the
> current and allowing the energy from the coil to be dissipated over a lon=
ger
> time period. Lowering the peak spark current also reduces the EMF emissio=
ns.

You were doing fine up to this point. In an L-R circuit, the time constant =
is
L/R -- in other words, adding resistance makes the time constant shorter, n=
ot
longer. Also, any resistance in the wire forms a voltage divider with the
resistance of the arc, reducing the available energy at the arc. AFAIK,
resistance wire is used only for EMI suppression, as early car radios were
poor at rejecting it.

-- Dave Tweed
--=20
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