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

I just found this page, but the way he says to break in the engine goes against everything I've heard about how to do it, both here and elsewere.

Thoughts?

 

If you think about it, it all sounds pretty accurate, and the pics do say a thousand words if they in fact have not been tampered with.... Wish I would have known all this before I broke my engine in "easily" 2 months ago and i'm now going through a qt of oil every 400-500 miles....

 

As noted there it's a contraversal subject that'll get a variety of answers. I know plenty of dirt track racers that dont have a chance to "properly" break in a motor. They usually slap the thing together, break in the cam, load it on the trailer and head the track where it gets the snot beat out of it. My freinds dad builds his engines that way as well. Witnessed 2 of the builds for his 2 sons and both were pulled into the street after cam break in and dad told 'em to let it eat. Both engines held up to multiple years of bracket racing/street driving and only had 1 piston go south from pre-ignition. The motor that's sitting in my car got the "baby break-in" with the slowly working up to speed, and the 40-60% throttle then back out, then worked my way up to hammer time. I've got 2 years of bracket racing-lots and lots of passes, can only guess to be in the 1200-1800 range, and lots of street miles. Right now there is some smoking issues that I'll find out about later when I get the new mill installed and build this one for a back up.