What is your hot oil pressure at idle? What is your idle speed? What oil are you using?

My stock LS7 would dip in the low 20s when it was really hot. My new engine is as low as 12 psi so far (650 rpm). I’m still on conventional oil for break-in (10w40, I think) and will be swapping to 15w50 or 20w50 soon. Before I dump another $100 worth of oil in it, I thought I’d get input from others with looser engines.

My forged LS7 will idle hot at around 25 psi at 800rpm with Amsoil Z-Rod.

There is a really good thread on here by a mechanical engineer(SAE)who works for and does oil testing, it’s a lengthy read but he has posted data on over 200 different oils that were tested by mechanical/chemical engineers all SAE guys. I found it very helpful because it’s 100% test data no opinions or speculations just real scientific test data. Break in oil is a terrible choice, not my opinion just going off the numbers. His simple recommendation is use an oil with the highest PSI wear protection, no matter what, break in or not. I’ll look around and try and post a link. Another good point he makes and the data proves is an oil can’t provide wear protection and at the same time allow wear for a break in period, it’s just impossible to do both.

It’s a sticky in the C3 section but here’s a think to the thread.


https://www.corvetteforum.com/forums...test-data.html

Break in oil is a terrible choice for what? For wear protection? Of course it is. You touched on that in your last sentence. All of the information I’ve read states break in oils/additives are to _allow_ the parts to wear together initially. I didn’t read the entire thread you linked because it seemed like he was writing to an audience that thinks high zinc oil/additives are useful beyond a break in period.

The rest of the article says you can’t stop or prevent moving parts from wearing, they will wear to the tolerable amount regardless of break in or oil or not. He does go off on the whole zinc thing which I could care less about. Basically break in oil has awful wear protection and the parts that need to “break in” will automatically do that, will the break in oil do it faster? Sure because it has awful wear protection and an oil with outstanding wear protection will allow and can’t prevent parts from “breaking in” so running break in oil is only a dangerous gamble is basically what the rest of the article says. It goes on to say pick any of the top 50 that match what you need for weight and viscosity and stick with it.

Yeah bro I don’t....I am an electrical engineer and have a good bit of friends who are mechanical and chemical so I’ll go with those guys on what’s best and what’s not. Do any new cars come with “break in oil”???
Anwser is no, so you can buy into or believe the marketing or do your own research and make an educated decision on your own, I could care less, your money your car.