See my post #5. The primary resistance is too low on your coil. The MSD-8222 is the coil you should have. Pro-comp recommends 0.5 to 1.0 primary resistance. Also does your ignition switch wire going to the coil have +12 volts all the time. Older chevys had a resistor wire from the switch to the coil. After starting the volts are reduced to 8-9. If this is your case run a new +12 volt wire from the switch to the coil. Here is the wiring diagram for the 7000 series.
http://www.store.procompelectronics....PC7000INST.jpg