Well got a response from MSD here it is
"Sir,
Some of the coils can make some noise. It is created by the output of the coil which actually transfers to the metal bracket. The fix for the ones that ones that buzz or hum is to actually place a small rubber grommet between the coil and the bracket where the bolts go through. This will solve the problem.
Thanks,
MSD tech
-----Original Message-----
From: Frank W [mailto:]
Sent: Monday, October 15, 2001 9:18 AM
To: Joe LaPille
Subject: MSD TFI blaster coil noise
I recently purchaced a MSD TFI blaster coil for my 90 Mustang 5.0 This coil makes a buzzing noise that is audible from the drivers seat when the car is idling, the original Ford coil does not make any audible noise. This is a pretty unacceptable issue as this coil does not provide any real performance upgrade other than replacment of a 11 year coil.
If you have any technical fixes available I would be interested, otherwise I will ask for a replacment of this part."
I have not had the time to try this out yet, pretty easy to do, in their defense the stock coil has a plastic/rubber coating on the metal "hoop" which eliminates the direct metal to metal contact at the mounting bracket while the MSD is metal to metal. Maybe tonight I'll try it out
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Frank W 90 5.0 LX Notch MAC 2.5"cat bk FMS alu ds, MSD coil, MAC shifter 2.73 gears
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