Motor Break In

[agro1]

Taking delivery of a a new SPF w/a 351 stroked to 427. Now I know there are two schools of thought about the proper way to break in a fresh motor:

1. Drive it like you stole it;
2. Baby it for [approx.] 1000 miles.

Any thoughts would be greatly appreciated.

NEVER LIFT

[Back in Black]

If there is a warranty, you should follow their instructions. If it's a Ford crate motor without warranty, you should baby it for the first 1,000 miles, and keep the revs 10% under max for the next 1,000

Then you can drive it like you stole it, if you aren't scared!

OH, and change the oil at 500 miles, cut open the filter and take pics if there are any really nasty pieces or shards ! save the evidence if you have a warranty!

[Mr.Fixit]

Change the oil at a couple hundred miles, cut open the filter. If everything looks good, go for it.

[wadesdad]

agro1,

The link below shows break in procedures via Crane Cams web site. My builder suggested keep it over 1500 RPM - varying RPM for the first half hour between 2500 and 3500 RPM. Then change the oil after 1 hour or 100 miles.

-wadesdad

Crane Cams Installation Instructions

[wilf leek]

For what it's worth, my engine builder advised keeping it under 3000rpm for the first 500 miles, then 500 rpm up for every additional 100 miles . Cam break in was not an issue due to its being a roller type. Plus usual stuff like not letting it slog, varying the revs on longer runs etc.
I found that full ring seal (and hence oil consumption stopping) didn't really happen until about 5000 miles, and I had surely been using the full rev range for a while before that.