Changed Map sensor, O2 sensor, Egr valve, spark plugs and distributor cap and rotor, fuel pump, fuel filter, got the radiator running right no overheating, relays,
but it drives alright on flat roads not really any power but when I hit a hill it shifts hard and makes my engine run high rpm and no power and after the hill my engine runs terrible after that
After 35 years almost anything could be wrong with it. Did you install OEM parts, particularly sensors and fuel pump? Check pressure at the fuel rail? Checked fuel injector operation? What did the spark plugs look like? You mentioned in a previous topic that the engine had overheated - possibly more than once, have you checked for a blown head gasket? Performed a compression or leakdown test?
@chucktobias if it was an head gasket wouldn’t the oil be milky and my oil is alright for now till I find this problem
Sounds like your transmission is on its way out. Check for leakages. My '79 Pontiac has a very slight transmission leak. Check all rubber parts. If that transmission's torque converter is all original, the rubber seals are most likely dry rotted. Transmissions that are low on fluid will slip, especially on inclines. It's almost 35 years old, after all.
@justin-shepherd fluid was a little dark but I dropped and filled the fluid and no debris on my magnet
@justin-shepherd you think it could be a bad Transmission Modulator Valve?