1994 Acura Integra Engine chokes

I have a stick-shift 1994 Acura Integra RS. After driving for some time when the car is warm the engine seems to choke. It happens at any speed in any gear, usually after 2500 RPM. It feels like if something blocks the cold air intake for a second and the engine just chokes because lack of air. A second later the car will just shoot out and continue driving normally. This starts happening when the car has been driven for a while and the engine is hot, when I first turn on the car and drive it around for a good 20 minutes its fine. Ive Changed fuel pump, ignition cables, air filter, spark plugs, fuel filter, distributor, MAP sensor, TPS sensor, Speed Sensor. Motor runs good and strong. I've heard it could possibly be a clogged cat, short circuit in my harness, bad ECU, or problems with my ignition. Any Ideas?