Break-in Oil

My 351 is being rebuilt and need recommendations on break in oil. Shop is willing to sell me some at $7 a quart, but want to know if there is somthing cheaper that will do the job. I want to properly break in the engine, but still on the high side of cost.

Thank s

The last engine I had done was broken in on Havoline 10W30. First oil change at 1000 Miles. Normal service after that. That was 100K ago.

I'd feed it a nice steady diet of Shell Rotella T Synth and make the first change happen with less than 1000 miles with normal service after that. This is assuming it's a flat tappet 351 and not some roller cam setup, if so just about any oil will do because the ZDDP requirements are going to be lower and still have safe cam lobes and lifters.

Use straight-weight conventional of any brand (so like a 30W) that's non-detergent and add a bottle of the ZDDP (GM sells some good stuff, as does Redline, Royal Purple, etc). As soon as break in is finished change the oil and filter with a 10W30 and another bottle of ZDDP (it's usually just a half bottle per engine so you can use half on break-in and the other half now) and drive 500 miles at varying speeds/RPM's (stop-and-go, no highway stuff). Then change the oil and filter again with whatever you will use for the remainder of the engine's life.

For oil the general concensus of 30 wt non-detergent dino juice is spot on. I use that for 100 miles, do a change then w/ a filter, then again at 500. More than just the oil matters however; how you go about managing the initial break in is important. The first time you light it off, make sure nothing is leaking and when you have full operating temperature start out doing 1/4 throttle pulls to 1/2 of red line. Gradually work your way up to using the whole thing. Other than valve train components getting to know one another the main break in item that matters is seating the rings to the bores; to accomplish this there has to be some pressure behind them.

We used to test fire new race bike engines in the shop for a few minutes and do the break in on the dyno. A brand new engine would get a dozen pulls of increasing intensity and then the work would commence. They never used oil and they always had exceptional leak-down numbers.

This guy has pretty good info:

http://www.mototuneusa.com/break_in_secrets.htm

Yup, we use 30W non-detergent in the engines we build. And here's our recommend break-in procedure: http://flyinmiata.com/tech/breakin.php

Shell was forced to change the rotela formula last year.

Flat tappet motors use Brad-Penn oil. The old green Kendal plant still makes oil under brad-Penn Bradford Pennsylvania. It has the right amount of zzdp

Joe Gibbs has break in oil too. The break in oils are just that. Not really to be driven with in the engine?

I bought an additive from Comp cams that will do the same thing with pretty much any oil. Have yet to start it.

I thought the procedure was to start it and bed in the cam for ~15 mins. Change the oil and run the car for 500-1,000 miles an change again.

All that is being done is the bottom end (short block) My heads have very little wear that can be measured in hours and not miles. I will assemble the day after christmas and install into the car most likely over new years weekend. Testing will be the next few weekends after that.