[claypoolxx]

For a while I have been having problems with the oil pressure dropping at high rpms. I've changed oil filters and it seems to help. A purolator will drop down to 30 psi at 5500 rpm, a fram to 40 psi, and an ac delco only to 50 psi. I'm using doug's headers so I have to use a smaller filter. The ac delco number is pf58 and I think the fram is 3829. I'm assuming that the problem is oil flow. I have the angled oil filter adapter. Will porting it out some help? I dont want to use a remote oil system. Its a 72 400 60 over in a 65 lemans. Any suggestions?

[claypoolxx]

For a while I have been having problems with the oil pressure dropping at high rpms. I've changed oil filters and it seems to help. A purolator will drop down to 30 psi at 5500 rpm, a fram to 40 psi, and an ac delco only to 50 psi. I'm using doug's headers so I have to use a smaller filter. The ac delco number is pf58 and I think the fram is 3829. I'm assuming that the problem is oil flow. I have the angled oil filter adapter. Will porting it out some help? I dont want to use a remote oil system. Its a 72 400 60 over in a 65 lemans. Any suggestions?

[Superduty65]

What are you running for a pump? 50 psi still seems good to me. I'm sure others on this forum will help you diagnose your problem better than I, but as long as there IS PRESSURE, it would seem the motor is still safe.

[goatseeker]

I had similar issues with the Fram filter - that's why I've switched exclusively to AC Delco. They seem to work best for me with my combo.

[78T/A462]

I had that same problem a while back. When I would stomp it the oil pressure would drop down near 45psi around 5500-6000 rpm. It would also shoot my dipstick out. I pulled everything apart and it turned out that the clearances in the oil pump were off, basically the oil pump gears inside were worn and I guess had worn down. I changed the oil pump, slapped everything together and now anything above 3500 rpm I get 65 psi. I also use a PH25 fram filter. Hope this might help. Good luck!

[claypoolxx]

Thanks for the replies. The engine was recently rebuilt by a reputable builder in town and a new oil pump was put in. If it is the filter, is there anyting that can be done to one to make it flow better. I've read about people changing their oil bypass, would that help at all?

[Superduty65]

Just because it was built by a reputable guy doesn't mean he checked the oil pump clearances. You should ask him to make sure.

[Otto Tharp]

Stick with AC Delco filters. For a 3.25 main, the minimum oil pressure is 10 psi for every 900 rpm for safe use and I believe for a 3.00 main is 10psi for every 1,000 rpm.