Mallory Unilite Circuit Guard w/ Bosch Dizzy?

[frank]

I toasted my Ignition Control Module model while fixing my recent electrical problems... I know, I should have disconnected the dizzy.

So, as insurance in case I forget again and to provide a more stable spark I am considering installing a Mallory Circuit Guard however it has a resistor in it as does the Bosch coil. I am wondering if piggy-backing two resistors like this would create too weak a spark. Anyone know?

The alternative is the Mallory High Performance Active Power Filter which has no resistor.

For reference:

Mallory 29351 - High Performance Active Power Filter
Mallory 29371 - Circuit Guard (Same as 29351 but adds resistor)
Mallory 4554101 - Magnetic Breakerless Distributor
Mallory 605 - Ignition Control Module

MUCH Cheaper and BETTER replacements for the 605 ICM which are all manufactured by Mallory:

• Mallory 6100M - E-SPARKŪ Ignition Control Module
• Accel 2005 Points Eliminator Module

[frank]

According to Craig from the Accel Performance Group:

"If your Bosch coil has an internal resistor (primary resistance is 1.4 ohms or greater), than you do not need to add a ballast resistor to that circuit.

However, either the 29371 or the 29351 will add additional insurance to protect against any unwanted voltage spikes. The 29371 (circuit guard) is the better of the two, providing protection also against feedback, load dumps etc. on the negative side of the coil. The active power filter does great, but does not provide all the protection that the circuit guard provides."

So I'm going with the circuit guard.

[JimHoyland]

I always carry a spare module; burn't mine out from doing electrical work. Should have disconnected the unilite