I have a '85 Camaro Z28 with a 305 TPI. Recently bought & restored it. It runs good for about 10 miles and then the engine begins to miss and backfire through the intake manifold. When I accelerate, the problem gets worse. I have checked fuel pressure (runs 45 PSI at wide open throttle), replaced spark plugs, plug wires, cap/rotor, ignition coil, and ignition module. Compression check shows that it has good compression. ECM is not setting any codes. I would appreciate any helpful advice.

 

Even though you have replaced all those parts that does not mean one is not defective. Sounds like a heat soak issue with an ignition component. Usually its the pickup or the coil that have those kinds of issues. Since you did not replace the pickup I would check that.