1994 Chevrolet Lumina Engine issues

My car keeps cutting off and bogging out for no reason. I have replaced the fuel pump fuel strainer all the seals and have change the filter 3 times. I have put in new spark plugs and wires. I have put on a new passenger side axle and new motor mounts. It already has a new radiator. I have a new air filter that I just put in. I have already put in CRC fuel cleaner. And my car is still acting up. The water pump seems to be fine its not leaking it's full of antifreeze. All of my fluids are full and topped off. I honestly do not know what it could possibly be. All of my fuses have been checked and replaced all of my relay fuses / switches I have been checked and or replaced. Could you please tell me what else I could possibly do to fix the problem without having to take it to the shop? Also she seems to run fine until she gets hot enough is when she acts up it feels like my motor is going to fall out and I'm going to be thrown over top of it. Its not as bad as it was since I have put in two new motor mounts. She backfires and misses and seems to have no power going uphill sometimes its like something is clogged and she is not getting enough fuel.