So my engine builder is telling me that the engine should be babied and broken in without the turbo... Its an Amc 401.

Everything I've seen and read these days says to break in the engine as it's intended to be used. Which also seats the rings the quickest.

I'm losing sleep over this..

 

Not babied, but many break in na or on very low boost. You don't want a bunch of extra fuel in it while breaking it in. Much less worry about the tune na, and you can get some heat and load.

 

Seems odd to do it that way. Then have to go back and have the efi re-learn and or re-tune it over again.

 

Yeah, I take the wastegate spring out and break it in under a load on the dyno. Pull it to 5500 and then let it decel to 2500 or so amd then wot back up to 5500. I do this in sets of 4 followed by a cool down and check over, then fire it up and do it again. I do the 3 or 4 times followed by an oil change. Then I put the spring in and start tuning for boost because at that point I have the na tune down pat usually.