I have a question about breaking in a freshly built motor. I was running a partially built (forged pistons,rods,acl bearings)b20. My tuner told me to break it in on the dyno. So I took it to him with hardly any miles, got it tuned on low boost which is 10 psi. Ran good for a while but my rings ended up not seating right, I tore motor apart, ordered a sleeved block, swapped to built b16 head, and ordered new piston rings. Don't know what caused my rings not to seat right but my new block is getting honed. Should I break it in normal driving or while tunning? Thanks in advanced

 

I cant find the archived thread by Earl Laskey (the late great one) since the search engine here is about 96% useless at finding old threads.

The gist of it is the same as motoman's procedure.
http://www.mototuneusa.com/break_in_secrets.htm

 

Here is the Earl Laskey one, it's in the FI FAQ.
https://honda-tech.com/forums/forced-induction-16/new-engine-break-some-new-ideas-878397/

 

Ahhh forgot to check there, good looking out. Thats the method I followed for break-in and would recommend as it worked well for me.

 

Lots of hi Vac helps set the rings in. After you get it running(like within 5 min) go out and drive it. Take it from 2k-4k, and leave it in gear, let off the gas and don't touch the brake, and let it come back down to 2k on its own. Then go form 2k-4500, and let it come back down to 2k on its own again, do this in 500 rpm increments until you get up to your red line. I also give it 20-30 seconds between pulls to make sure I'm not overheating a new engine. Then bring it back home, change your oil and your good to go. I work it through the range a few times like this. In total about 20 min of driving is all you need to seat your rings. I did this on my 8.0:1 LS and im hitting 175psi across the board on my compression test.

 

Thank you. Very helpful