LeMans Pete

I have 6 quarts of break-in left from our motor start-up and cam break-in yesterday. I am changing the oil today and thought about using the 6 remaining quarts, running for a couple hundred miles before switching to a conventional.

Thoughts? Any concerns running break-in oil?

76strokervette

I would run the break in oil until you are sure the rings are seated then run what you like.

Rescue Rogers

It just has a lot of zinc and phosphorous so it wont hurt

firstgenaddict

You are supposed to run it for 1000 miles... that's what the AMSOIL REP stated when I purchased some a month ago.

fishslayer143

contrary to bubba mythology, your motor is not broken in after your 20 minute cam run.. especially if it was not built loose for track use. use that oil for 500 miles.. vary speed and load .. no extended WOT ..hills are excellent for break in seating rings.. load going up, engine break going downhill .. change oil /filter at 500 miles to whatever you intend to use from then on. I personally prefer synthetics. Several brands have Zinc for cam. Then drive it anyway you like.

jackson

Flat tappet cammed L46 right?

The First short run knocks off the bigger chunks ... then go ahead & change oil AND filter ...
... refilling with that break-in oil ... Second run polishes off the smaller bits and you can run that 500 -1000 miles ...
... Lastly, change oil & filter again ... this begins your regular schedule so refill with whatever you'll routinely use.

Run whatever oil makeup you want, but ensure it has ample protection for your flat tappet cam.

jackson

here is install guide for chevy performance 350HO ... has a hydraulic flat tappet cam ...BREAK-IN procedure at page 6

https://www.chevrolet.com/content/da...e-19210008.pdf