This is a characteristic of the car and is not a malfunction.
You cannot bypass enough oil through the pressure relief valve cold to affect this. If you modify the valve to drop that much pressure cold you will have low oil pressure at high RPM hot and it will result in engine damage
I think you should be more specific. It is the function of a pressure relief valve to bypass oil above a set maximum pressure. I didn't see anything about modifying things.
Having just viewed your little youtube vid I must say I'm inclined to agree with Windsock. Maybe marginally high pressure on that very first wee rev, but it seems to normalise within the 30/40 seconds you run the car and by the last rev 3k+ it seems entirely normal to me.
Exactly. You can see it certainly works - idle pressure is at 90psi and it even bypasses enough up to about 1500rpm - but seems overwhelmed beyond that. As I said, pressure never goes over 90 once the oil is hot. I'm willing to accept it as a quirk of the 360 but I really don't think this would be considered "normal" in any other car. I can't see how a bigger bypass hole would cause any negative affects and it would reduce/eliminate the pressure spike. EDIT: To be clear, I'm not suggesting actually making any modifications.
There is no way you will bypass enough very thick 5/40 engine oil through the small bypass valve spool at speeds above 3000 rpm+ when cold. The engine oil is much thinner at normal temps and not only bypasses through the spool easier it also bypasses the bearing clearances and oil pump clearances as well. I offered my opinion based on the thousands I have experince with by all means do what you feel is necessary to feel comfortable but if you bypass enough oil when cold to maintain oil pressure bellow 120 at all RPM you will have oil starvation and low oil pressure hot. good luck
I appreciate your input as an experienced expert. I'm not changing anything, as I clearly stated in my last post. Now that I understand it's normal, I'm waiting for parts, and it's accessible anyway, I'm simply curious why it behaves the way it does. It turns out the relief hole is never fully uncovered. As long as the spring rates stayed the same, I can't see how allowing the piston to move farther would affect anything when hot. It seems like an odd design decision but maybe more area of the relief hole is uncovered than exists in the piston so there's no advantage.
