Is the engine actually turning over? The passlock system will alow the car to start then dye and the security light will either flash or stay on steady. If the security light goes out once cranked it is good. Test fuel pressure at the test port with a guage. It will need at least 35 psi. How do you know the head gasket is out? If it is leaking internally and the engine is not turning over it could be hydro locked. Use caution cranking it over if it is hydro locked it could bend a connecting rod.
Another helpful thing is it a 4 or 6 cylinder?