Question on my oil pressure readings-happy father's day
Well I won't be able to tackle it till Wednesday but even so is the 1000 rpm 10psi rule still good to go by? Just in case my results don't change is that still bad numbers? When I built the motor all the tolerances were .0015 so I thought I was on the tighter side that's why I just stepped the up to .0025 cause I thought I was making a good move on my part? If that's what's causing it to be on the lower side then should I run it or possible looking at pulling motor to replace bearings soon to tighter tolerances?
Even at .0025 with a HV pump you should have enough volume to get the pressure higher than that at idle.My biggest concern is the bushings in the rockers don’t have enough oil up there to keep them off the shafts. It’s not like a stock stamped rocker where they sit in oil, or a needle bearing that can run much less oil.
The 10/1000 rule is ok if you understand when to apply it. Some engines can (and do) use much less oil pressure. I was consulting on a MFI SBC on a dyno and at 8500 they had 48 pounds of oil pressure. I didn’t say anything because I wasn’t getting paid to question the build, only to unscrew his injection. After 60 pulls on the dyno it came off and I looked at the parts. Looked like they all just came out of the box.
I was running my junk to 8500, and had I run my oil pressure that low it would have exploded before it was at 6500. My stuff looked the best when I had 100 plus PSI at 8500. Both of those examples violate the 10/1000 rule.
If you go to a higher grade oil, you are just increasing the pumping resistance, not the volume of oil. If that makes sense. IOW’s, your pressure WILL go up, but not because you have more volume of oil moving through the system. It will be because it’s harder to pump that thicker oil. It’s resistance to flow.
Everything I’m building (and it’s not much anymore) is set up to run thin oils (its all about flow because flow means more oil passes through the engine and that oil cools many of the parts its lubricating) and tighter clearances.
I think I’d run what you have for a while and then pull a rocker shaft and see if it’s leaving bushing materiel on the shaft. If it is, you’ll have to fix it somehow. If it’s not doing that, send it and go run it’s guts out.
