100-plus lbs oil pressure problem

[dsmith]

I have an ERA with a 428 that has developed an oil pressure problem.

I went out to start it the other day and after it had been running for about 20 seconds I heard a squeal, sounded like a fan belt. Looked down at the gauges and watched the oil pressure guage drop to zero. Killed the motor and got out of the car. Oil was pouring out from underneath.

Towed the car down to my buddies garage and got it up on the lift. Turns out the gasket on the filter was blown out and all of the oil drained from the motor. Bottom of the filter was domed - rounded, all the dimples around the edge had been ballooned.

We put a new filter on and filled her back up with oil and watched for leaks. there were none, so we started the car up. Oil presure went up to 95 lbs at about 1500 rpm. When goosed a little, maybe 2500 rpm, it shot up to 100 lbs of pressure. At idle it is running about 70 lbs. Once again the pressure was so great that it expanded the base of the oil filter blowing it out out to a round shape.

What would be causing this? While I never actually recorded the pressure, my recollection is that the car has always had about 30-40 lbs at idle and I know it never had more than 60 when revved up or running on the highway.

This is a new car for me (1983 with recent rebuild on motor by previous owner, 700-800 miles on rebuild) I have driven it from his house to mine when I bought it (70 miles) and on a couple midnight rides since it is not yet registered. Everything has been normal.
Have been starting it on a regular basis all winter and the pressure has been normal until this past episode.

I would greatly appreciate any help/advice. We are going to take a look at the oil pump today, but I can't understand why it would be so high all of the sudden.

Is there a spot that there could be a restriction? I have checked the filter in the line to the oil cooler and all is fine there.

thanks

smith