Breaking in Your Rebuilt Engine

[MaxClass]

Their seems to be a lot of different worlds of thought on this subject and I think I've heard most of them. After reading the information found at the following site and talking to many high HP builders this guy makes a pretty good case.

Take a look at this and let's get some feedback going with all the pros and cons you can think of. It is a critical aspect of ultimate engine performance and long engine life.

Check it out: http://www.mototuneusa.com/break_in_secrets.htm

Max

[EvanH]

I have been thinking about this too. IPO and Matt say it is good. But one thing that is mentioned all the time is how they are for race sessions. I just want to know how the longevity of this method plays in. And so far I dont know of any life expectancy other than the season of racing. I mean I may be wrong but it is something I am curious about. My friend who is a certified mech says to do it the way the mfg says.

But those pictures do look good. I am curious about it too.

[i3igpete]

the question i have is, has anyone ever actually purchased this guy's ebook? it seems like everyone on the internet suggests this guys website, but he doesn't seem to have reference to any SAE/ASME/tribology journals with real measured results.

[BaadVR4]

Without writing a book, there is nothing new in this article. With minor changes to account for a 1/4 drag race engine/car, virtually everything he says was stated by Chrysler as long ago as 1960. Cylinder ring "wear in" is accomplished by loading the rings, then reversing the load by "engine braking". The reason for long break in periods is to limit the heat build up which can cause cylinder wall glazing during break in. In a racing engine, broken in on a dyno or race track, this is limited by the short run times and cool down periods between "pulls". There is a fine line between honing too fine and too coarse for proper ring/block wear in and I doubt the "science" of cylinder block and piston ring materials has changed enough to make a big difference in successful break in procedures.

[Trab]

I always cut the boost up to 22lbs and dump the clutch in the first 10 seconds of startup...

[MaxClass]

If you could count the number of times that each piston goes up and down in just the first ten minutes it would amaze you. How many times must it do this to seat the rings? Does it have to be under a load, etc?

He says the rings are seated within the first 20 miles so you don't have a lot of time to get the job done. The performance machine shop doing my short block says the same thing.

Especially if you are building an engine specifically for the track you don't have time to go put 1,000 miles on it to break it in first.

I have also heard that you should change the oil and filter within about 5 minutes of starting it up. Start up with the cheapest oil and filter because your gonna trash them almost immediately.This will dump any burrs and metal chips from any machining that may be loft over. Then put in the oil your going to use for break-in.

Also do not use synthetic oils for break-in they are to slippery and will inhibit the break-in process.

At the end of this thread I'll put together a sequenced list base on the site and all/any feedback. Maybe Nelson or Matt have a few pointers on this topic.