mitchntx

Background ...

95 LT1
500 miles on the shortblock
Painless wiring harness (2 previous cars had no issue)
OBD1 PCM with stock tune
Car was in a fire and melted all wiring under the hood
Car idles well and pulls normal up to 4200
Car will begin to sputter at 4700 after the motor is up to temp
Can't read any codes for several reasons.
New plugs (NGK TR55) and plug wires (MSD 8mm)
"287" knock module

Car fired immediately and ideled well for about a minute and then abruptly died and wouldn't refire. No spark confirmed.

Changed the coil (new) ... still didn't fire
Changed the Ignition module (used) ... car fired and idled fine

Went to the dyno and the car consistantly lays down at 4200. The dyno graph shows a "saw-tooth" pattern as the power drops.

At this point, we are thinking it's the Opti-Spark. Does this sound like the most likely suspect?

The Opti on the car was the one that went through the fire. All the connectors and physical condition of the unit appear to be fine. There were no exterior signs of damage. But, it's been a year since the motor ran.

Does this appear to be sound logic?