surges badly when floored

1984 22r, starts and idles fine but under heavy acceleration it surges badley. it will rev to around 3-4 krpm and stumble and will continue to do this in about 5 second intervals it seeme to happen only after opening the secondary throttle. i have done everything to my knowledge to remedy this.fuel pump, filter,egr,pcv,coil,checked all vac hoses and sprayed manifold areas for leaks with carb cleaner, changed the carb with the same results, installed new secondary accelerater pump. i'm ready to drive it to the salvage yard . thanks