Classic/Antique Car Repair: Low Oil Pressure, low oil pressure, head gaskets


Question
I have a 72 Vette Roadster with a 350 small block from a 69 Chevelle.  The oil pressure as measure by the installed guage goes to around 40psi when the vehicle is warming up and then drops to below 10 at idle. If the accelerator is pushed, the oil pressure stays up.  I suspect the oil pump. Could it be anything else?  How do you replace the oil pump on this engine?  Any downside to a high capacity pump?  BTW, the Chevy expert is on vacation until 30 Apr.  Thanks, Kevin

Answer
Hi Kevin:
On an old Vette, this is normal. The old vettes took at least 5 minutes to warm up and get the oil pressure to a normal level, so 40 psi is normal for the first 5 minutes or so, then it would go back down to normal. This had a lot to do with the 350/305 engines and the way the head gaskets was designed. You can replace the oil pump, but not sure if it would improve the warm up and oil pressure readings.