Here is a link to an article in "engine builder magazine". There is a lot of great info, and it's clear that opinions vary even among pros. https://www.enginebuildermag.com/20...le will complete the,to a synthetic motor oil.
I see they mentioned the ILSAC GF5 oils which are API rated while claiming they have 'minimal' flat tappet protection. They didn't mention that the minimum amount is all that is necessary and more zinc ppm wouldn't be needed. Solid article showing the different opinions but I don't see it being really useful as a source to actually find the right break in procedure because of that. Nothing wrong with it of course, good way to explain how different people see oil, but I do wish they had a little more actual data to support either side of the argument.
Thanks to the PO of one of my cars when they installed a new short block they did not do something correct and the cost was a wiped out Kenny Bell cam.
I used regular oil with GM EOS back in 83 with a Comp Cam 268 I didn't know about running engine to 2000 rpm for break in I let it idle and nothing ever happened I guess you will be ok With Regular oil.
I am the poster who refilled after the 20 min breakin with a breakin oil. Break in the cam for 20 minutes. I drain the oil and do a refill. And I run the car for 400 to 500 miles. Seat the rings. Set up wear patterns. Seat the valve face to valve seats. Put loads on it. Put some wear on the running surfaces. Then Do another drain and fill. Me I probably would not go to a synthetic that early in the breakin. I’m sincerely glad it works for you. Heck I didn’t got to synthetic on the 5.3 until it had 20,000 miles or so. I think I am at 426,400 on it right now? Same long block on a mild tune and 87 in the tank…about 250k miles ago…So I believe what works for me……..does really work for me. There are a few good ways to break in an engine correctly and get a years of a good service life. There are just as many ways to get 15 minutes to 3 or 4 hours of service life out the same engine architecture….. Read about it here quite a few times. I hope your build and breakin works out good for you…
If it works for you by all means keep it up, I'm not here to tell anyone to switch what works for them, but wanted to post the real research I had compiled that may be helpful to someone, or just to share what was extensively tested. I just didn't like how quickbuick called someone an idiot when he himself has absolutely zero data to back his comments.
I used to do the same thing, I never brought the RPM up to two grand, just let it idle, maybe winged it a few times, BUT always had the GM EOS in it!
