Quote:
Originally Posted by Dezoris
I think its critical for people like yourself to be sharing data because you are at the extreme end of the limits. Based on what I have seen so far, even with conservative power levels, I just watch how the oil pressure has such a massive swing from high, medium low the hotter that oil gets.
I start seeing 60-65 PSI when oil is hitting 220F near 7200RPM and its worries me. However I have two UOA with zero wear material after track time so I think oil pressure is only one piece of the data.
I am going to try and start posting my stuff this next week.
Thanks for starting thread.
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If 60-65 is what people are actually seeing that's safe for probably up to 400 hp. The rod bearings are really narrow on the FA so I don't know exactly the pressure requirements until we are done with our engine R&D but on the EJ motor in the 60s we were skimming bearings at the 500 hp range. 70 psi and up is the target under racing conditions and under street conditions that's closer to 85 psi (We lose 10-15 psi from temperature).
NA guys just shouldn't worry much but it's still not a bad idea to run a high quality synthetic and to also run a cooler if you track the car. I would imagine even 45 psi is safe.
Now for those who are turbocharged or supercharged I found 350 was reliable under racing conditions but I was running 40w Red Line Race oil. This oil is really the best at staying in grade at high temperatures (staying at the rated viscosity) which will help with oil pressure. Supercharged guys may get away with a little more power since power increases linearly with oil pressure and doesn't have the early torque peak you get from a turbocharger.
Plenty of people are spinning bearings even with build motors and I have which is why I'm R&Ding oil pumps etc. Now I was running 400+ hp and 9k RPM with 325 racing slicks so given the data we are seeing it's no surprise to me I spun a bearing. For us to build a reliable race worthy engine we need to see a consistent 85 psi in street conditions and ideally 75 psi under racing conditions. I truly feel based on our engine and racing experience, nothing less will be reliable (at 400+ hp)
Thanks,
Phil Grabow