What kind of engine oil is good for the poor power of old cars?

Expensive products such as synthetic and PAO engine oil are definitely better than special mineral engine oil. Special or original oil needs to be replaced after 5000 kilometers. It's a bit bad to run for two or three kilometers. Fully synthetic Jin Mobil and Jin Jiahu can run at least 8000 kilometers, and PAO's long-acting GT engine oil can run more than 10000 kilometers, with better power. That is to say, it is suggested that 1.5 thousand kilometers or more old cars can use 30 viscosity engine oil, which will be more suitable for old engines.