I start my car up, and the OP is at 50-60psi idle And driving. Once it reaches operating temp (190) after about 15 mins driving, it drops to about 25-30 driving, 10 at idle. Im running 15w40 with a wix filter. New camshaft installed. Any thoughts at what could be causing the drop in oil pressure? Apart from the readings (which is on an AutoZone manual gauge), there isnt an issue with the way it runs or sounds

Olds 330 btw. Pic is my car.

 

Thats normal oil pressure. If youre worried, pull the filter and cut it open, check the filter media for metal. You might gain a few pounds with a higher quality gage.

 

Seriously? 25psi while driving is normal for these cars? If im following the "10psi per 1k rpm" rule, im only save to up to 55mph-ish

 

It's relatively "normal" for oil pressure to reduce when the viscosity of the oil reduces with increasing temperature. What you have doesn't sound like a problem. I can't tell what part of the world you're in, but if the ambient temperatures allow, and you'd like to maintain a bit more pressure, you could switch to a slightly more viscous oil. Try some 20W-50 on the next oil change and see if it makes any difference. I'm assuming that nothing happened during the camshaft change that would diminish oil pressure.

 

What was op before cam change? What all was changed, lifters, pushrods,etc?

 

Cams, lifters, and push rods. Op was pretty much the same before. The shop had put 5w30 in after the cam job and OP was the same cold, and like 0 idle, 20 driving when hot.

 

Put a quality gage on it and then see where its at.

 

10 psi per 1k rpm is not any sort of real rule.

Oil pressure needs to exist in enough amount to get oil there in sufficient quantity to lubricate.

 

If it's not smoking or ticking, just drive it and have fun!

 

I had something similar happen on a debry engine. I forgot to put in the oil pump rod and it ran with no oil PSI for a few seconds until I realized wtf was going on. Wonder if the mechanics did that.

 

As 70W-32 posted, it's not a "rule" but a general guideline for overall engine health (wear on the bearings and such) and I don't think it applies to revving to redline.

 

He has oil pressure , so that cant be a possibility.

 

If the OP was the same as before, and the only thing you changed was the cam/lifters/push rods, why would you think the OP should be higher now? Its not like you have a freshly rebuilt engine with new crank bearings and oil pump. Your OP numbers sound similar to mine w/ 120,000+ miles on it.

 

I appreciate all the suggestions guys, keep them coming. I really like the "it's not a problem" ones lol. Im just used to running 20psi idle, and 40psi+ on my cars. I could accept the 25ish psi while running if I wasn't getting 3k+ rpm on the highway

 

i was just answering a question

 

@ 70w32. That scenario didn't entirely kill my oil pressure. I had a little over 0 at idle and 25 max psi. Before that was a derby engine I flogged it on the street with no issues with the same oil PSI.