In short, I blew and engine, rebuilt it, found metal in it after the break in, tore it completely down and rebuilt it again with the same cam and (cleaned) lifters and rings. I did not necessarily put the lifters back in the same place they came out. Does the motor need a break in procedure again? I suppose it couldnt hurt but I thought Id ask.

 

What form was the metal in? I ask because it's normal for oil to contain fine metal particles after the break in, so that it looks a little like metal flake paint before spraying; that's from the cylinder walls/rings and bearings breaking in.

Since this is in the LT1 forum I assume you're talking about an LT1; if you have roller lifters like the stock configuration there isn't really any break-in on the cam like with flat lifters. Those break in to match their camshaft and have to be kept in their original positions, or rapid cam and lifter wear is likely.

 

I guess I should be pull my 383 back out of the Vette, You should find some metal after break in. Run it......

 

If it has new rings and brgs then break it in like a new engine.

 

To be honest I would be easy on it for a little while. Roller lifters aren't as bad as the old flat tappets, but they do put a wear pattern into the lifter bore. Same thing goes with the bearings. I don't think you need to go a full 500 miles or anything, but I wouldn't beat on it until you get a hundred miles on it or so and change the oil.

 

Break-in should be keeping the RPMs between 1500-2000 and varying the RPMs, i.e. don't just take a long cruise keeping the RPMs steady.

Note: Everyone has a different idea of how to break in a fresh engine, much the same as everyone has their own idea of what lubricants to use, etc.

I once drove my new MGB a straight 500 miles going no faster than 50 MPH on turnpike from Phili to Michigan---believing at the time that it was the right thing to do. It sure took a long time and I doubt that it was the right way to do it.

Old schoolers often said that you should break it in like you intend to drive it. One the one hand, if they meant that you should keep it within the RPMs that you will usually drive (between 1500 and 2000 RPM---sounds reasonable----however if you intend to drive the $h...out of it---I doubt that that particular method of break in would be the best way to go. JMHO

 

Agreed, but this is how I broke in my engine and it runs great:http://mototuneusa.com/break_in_secrets.htm

I sent the oil to a test lab for analysis after 1200 miles (http://www.blackstone-labs.com/index.html) and it came back with normal results.

So, you can put me in the fast break in side of the discussion.

 

Ditto. It has been a fun break in compared to babying it.

 

Break-in for me was alot of fun too.

 

Beat the **** out of it. That's what I did.

 

I have built engines, dropped them into the car, filled the cooling system and pull them strait onto the dyno for some full throttle runs

this works fine for roller cam motors, since all that needs to break in is the rings, and high loads does it quickest

 

I agree with this way... Run it hard and seat them rings... after a few good blasts should be good to go. Change oil.

 

That web site makes good argument, although it doesn't "feel" like a trustworthy source. At least not just from looking at it.
But hey, it's the Internet, take it all with a grain of salt.

Having said that, we've always broken new engines in on the dyno.
"Break it in the way you intend to drive it" is what my old builder told me.
I have no evidence to support or refute that theory.

Assuming you change your oil and filter and get the dirty oil out, you should be fine IMHO.

 

digging up this thread because i plan on starting my 383 soon. that website did give a good guide as to how to break the engine in. but when he explains on how to break in for the street, does he assume the same % throttle method will be used from the dyno example?

 

We put the fluids in mine, got it mail order tuned (by now it had been idling for atleast a half hour to an hour. Once the tune was close, we took it out and laid into it. Still runs 20 miles later, oil had the typical break in shaving but nothing crazy. I sometimes think break in is looked at to much.