hill461
06-01-2014, 12:53 PM
Son installed a 6 al mad box in his 64 catalina it only ran bout 20 minutes . It appears by that the box has went bad by msd test . Do these old cars have a resistor ign wire and if so will it affect the msd box
Hill 461
2013 q16 winner
screamingchief
06-01-2014, 03:33 PM
Yes many older cars will have a resistor wire in the harness to the coil.
But I seriously doubt that the resistor wire would be the cause of a box failure as the box typically gets it's main power directly from the battery (big red/black wires),and the smaller wires are just "triggers" for the box itself and their voltage is far less important.
Spikes to the main power wires will certainly damage the box,thus MSD offers a power filter (capacitor) that is supposed to help prevent any surges or such from damaging the box itself.
Also excessive heat can kill them too.
And mounting orientation can too.
(Not supposed to mount them upside down as the box wont vent moisture then)
Honestly,a whole lotta things can kill them.
And if you're referencing the spark plug wires,yeah solid core wires can affect the box operation,but it still should'nt kill the box dead.
FWIW
Bret P.