I road race a 260z with a 240z engine. My oil pressure went so high that it blew out the oil filter at the seam. Is this caused by a stuck relief valve or are there other issues to check. None of my mechanic friends have ever seen this happen. Any ideas?

Most likely the oil pump relief valve. If your oil pressure gauge is working like a tach, that's it for sure. Could also be a plug in the oil system. Definitely must be sorted out before continuing. Change the oil pump first, easy to do or just diassemble the relief valve in it to clean and re-try.

That's exactly what the oil pressure gauge is doing. Thanks for your help.

It's nice to get good quick info when you need it.