[Bob Mulry]

Just some random info about MSD's & other high current draw parts...............

The MSD 7AL depending on the resistance caused by the plug gap, high compression, rotor gap, sparkplug wires, load, RPM and anything else that makes it more difficult to fire the plug will raise the amperage requirement for the box.

Your power supply wiring should be capable of passing 15 amps on the positive AND negative side.....

All wiring connections should have crimp fitting (mechanical connection) and be soldered (electrical connection) and be covered with shrink tube to prevent corrosion.....

You MSD box will work perfectly until you the reach the point of needing more amps than your wiring can supply...

Had the same type of problem with a MSD 404 box 40 years ago and learned my lesson regarding resistance in the power AND ground side of wiring..

In the words of Stroker McGurt "If some is good, more is better and too much is just right"

Hope this helps,
Bob