Because high oil pressure is good...
The normal oil pressure on a GM 305 engine is between 40 and 60 PSI depending on the model year. High oil pressure is needed to allow for proper circulation through the engine.
If you are losing coolant, you probably have a bad cylinder head gasket. Too much coolant system pressure will drop your engine oil pressure.
normal oil pressure is 48 to 60
The pressure will be high until the oil reaches full operating temperature.
High oil pressure is good....
A cause for high oil pressure could be related to the type of oil that is being used in the vehicle. Thicker based oils such as 10w40 and higher could cause high oil pressure.
If your oil pressure gauge is high you have to much oil in your engine. Overfilling your engine can result in you blowing out your gaskets.
There is no fuel injection pump the fuel pressure going to the injectors should be about 60 PSI then the injector does the rest. There is a high pressure oil pump which provides high pressure oil to the injectors however a switch monitors that and if it is low the engine will not crank or run.
first test pressure with a professional test kit a mechanical one let engine reach operating temp. this will be you true pressure, sometime the electric oil pressure sending unit is not compatible with your gauge and give a inaccurate reading.your pressure is way to high,did you put a high pressure race pump in? if not you have a bad pressure regulator valve in your pump 60 psi is plenty to much will start blowing oil seals
High oil pressure or a faulty oil pressure gauge.
The high oil pressure relief valve is located in the oil pump