Ok so I have a 97 Z28 camaro that stopped running and wouldn't start back. I've replaced the optispark, the ignition module and the control module ,and it still won't start. It just cranks and cranks.

 

You going to need a voltmeter and a manual, no reason for someone to type they step by step procedure when its in the manual in the linked manual sub folder at the bottom of the main page.

You replaced the control module and the ignition module? That is a neat trick considering the full name is the ignition control module (ICM). There is only one.

1997 CHEVROLET CAMARO 5.7L V8 Ignition Control Module (ICM) | RockAuto

 

test fuel pressure, pick up a noid light and see if injectors are being told to fire