The gold standard for many years was GM’s EOS (engine oil supplement). You can still get it but it’s not the same formulation. The good EOS turns up on eBay every once in a while but when it does, it’s always at a premium price.
I switched over to Bradpenn’s break in oil and have use it on quite a few rebuilds without a single failure. The brand is now called Penngrade but it just a name change. There are a couple of other companies that make a specific oil for breaking in a new motor, Driven I think offers one. But frankly the bradpenn has been a very good product and no failures so I stick with what works. Give it a go I think you will like the quality.
Last edited by Dragsix; 04/29/2020 7:24 PM.
