I coat the rings with Akerly and Childs ring lube, the cam, lifters and bearings with moly assembly lube then fill the pan with non -synthetic straight 30 weight conventional oil. This is break-in oil not to be placed in a high load, high RPM situation. Once the engine has been run for several minutes, while still hot, is then drained, the filter removed and cut apart for particle inspection.

I replace the filter and re-fill the engine with either 10W-30 or 10W-40 Synthetic Mobil-1 or Lucas oil depending on the weather. In colder weather I use 10W-30 but during the hotter summer months I change to 10W-40.

The next step is to check the valve adjustment, set the timing load up and head to a race.

I've used this process for several decades it has always quickly seated the rings, and I've never lost a cam or the lifters. For more than 55 years I've built my own engines, both drag race and circle track engines, never had the process fail.

Use what ever process has been successful for you, it's your investment of time and money. The process I've described has always worked for me.

Bob

Even when carefully assembling a engine, in a engine room, bits of stuff, that can cause damage exist. There is always a certain amount of “in place machining” on first fire. That’s why I recommend an initial no real power oil change. I used a system 1 filter and saw it every time.

quote:

Originally posted by Larry Woodfin:
J R, do you go to the track with the break-in oil?

I did on this last freshen, but usually I don't. I don't like to race with that oil, even though my engine man encourages me to... its thinner then what I normally use and I don't care for the way it looks with alky in it...

Some of this reminds me of a football player who is known for his catch phrase, "Come On, Man!"
Listen carefully, fellas. There is no more critical oil change in the life of any engine, than the first one. Period.
True, there is a difference between the first fill after a "Freshen" job (Rings, Bearings, Gaskets), Vs. a completely rebuilt engine. After a freshen-up, reusing same pistons, cam, lifters, etc, I have not seen nearly as much metallic from the initial oil fill at the first change, but I still don't run that first fill down the track. And as for a full overhaul, I would never even consider making a full pass on the "break-in oil". Like some mentioned above, the parts are mating and "machining" themselves to match. Run-in or dyno an engine for 15-20 minutes, to reach operating temp, then drain it and take a good look at that pan of oil in sunlight. Yeah, it is some really shiny stuff. And no, your filter is not keeping any of that metallic stuff you see out of your oil passages, otherwise it would not be in the drain pan, it would be in the filter. (And there is plenty of it in the filter, trust me). That run-in oil quickly changes from a wear preventive lubricant, to a wear-producing agent. If you spend $5K, $10K, or $20K+ on an engine, why would you even think about breaking it in, then going to the track with that same oil in it and make a few passes? Sure, it probably won't toss it's cookies that day. But in terms of longevity, (meaning giving you maximum performance for several seasons), and years of service with only an occasional freshening, I don't think you'll find too many "experts" who would agree with your saving $30-60 bucks as a wise area to reduce costs.
Go ahead and change it, then make 5-10 passes, (no more than 20), and change it again. You'll see WAY less metal-flake in that 2nd drain. It really does make a difference. Check it out. I sincerely believe your rings & bearings will last longer, and stay tighter, your cranking compression will stay higher, longer. And your oil will stay cleaner on subsequent intervals.
This applies to street vehicles as well.

As for which oil, it is pretty much common knowledge that full synthetic oil does impair the sealing of the rings/bore. I use non-synthetic "dinosaur oil" (VR1 straight 30 weight) for break-in, then go to Full Synthetic VR-1 for racing. Not always easy to find, and there are many other good race oils. Depending on clearances and ambient temps, I use 10W30, 20W50, or a blend of the two.

5w30 or 10w30 Valvoline dino oil, 2 heat cycles then hammer it down the track, 2 runs break in, 3rd run is the permanent dial, change it when you've got 15-20 runs.
Standard rebuild for a street car, 2 heat cycles, then accelerate @ W.O.T. 0 to 50 mph 5 times, break in is done.
NO ENGINE OIL on the cylinder walls for assembly, just WD-40 or the Total Seal dry lube. This is for any modern moly face ring package.

Driven