Larry,
At 09:51 AM 10/22/99 -0400, Larry Paulick wrote:
>Bob, the new MSD 6AL now has a warning in their instructions re the
>solid core wires.
Strangely, my MSD Installation Instructions say nothing about the ignition
wires. It's been so long that I don't remember the source of my
information, but the only issue I was aware of was the effect on idle
versus higher rpm operation. Adding resistance increases the spark duration
and the expense of total energy delivered. I used resistance (carbon
center) wire between the coil and distributor and solid wires to the plugs.
The short length of resistance wire improved low rpm - basically idle -
without sacrificing much high rpm punch. Now that spiral wound (inductive)
solid core wires are available, you get the increased duration without
energy loss. Ford Motorsport has a nice set available for about $50. Others
like Jacobs, ACCEL, etc. also have the fat, silicone, spiral wound type -
in assorted colors even. I think the spiral would wires are standard
equipment on some if not most newer cars.
It seems strange that MSD didn't discover this problem for several years.
Maybe the FCC got on their case about rf emissions or something, or their
newer circuits are less robust.
>Also the Mallory magnetic distr advises that with a MSD, you need the
>ballast resistor in the circuit, if you return the wiring back to
>original. Makes sense.
>
>Larry
Right. If you kept the same 9V coil, or replaced it with another 9V coil,
then you still need the ballast if you take the MSD out of the circuit.
This is true regardless of the particular distributor you have or whether
it has mechanical or electronic points. It is important to use the right
coil with the MSD - one that is suited to its very fast rise-time. This
means one that would have a relatively low voltage output without the MSD.
I makes sense to buy the coil from MSD since it would obviously be matched
to their unit. I would guess that it would also be a nominal 9V coil since
that would be the typical application in the US. However, I am using a
Bosch 12V coil and it seems to work very well, although probably not as
impressive looking (or as expensive) as an MSD one.
Now, what was Mike's problem again??
TTFN,
Bob
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