I have a fresh 383 build with around 1100 miles on it. I have chromoley piston rings which i know take a bit longer to break in. How will i know the engine is broken in? Will it just stop smoking? It dosent smoke much, just a little faint puff every little bit.

 

With a flat tappet cam, it's broken in after you do the cam break in. With a roller cam, it's broken in within a few minutes after you start it.

 

yes but the piston rings are one of biggest reasons for proper break in. how will i know why they are broken in?

 

A flat-tappet cam is the biggest reason for proper break-in. Rings are fairly forgiving of procedure.

 

So your telling me that if i go to my car right now and burn the tires down at 6k rpm, my rings will seat just as good as if i babied it?

 

Its what they said basically! You just know! Now its time for the good stuff....All the synthetics and all the performance enhancers! Please, whoop on all mustangs whom stand in your way, that wont be too hard!!LOL

 

they seat better when you hammer down on it. Do it early in the engines life with alot of engine braking to build vacuum in the crankcase. Helps force the rings out to the bore to properly wear into the bore shape. Thus it breaks in faster.

I would say 1100 miles is good to go race. I was racing mine after 75 miles or so...probably much less than that. Thats about how long it took me to tune the motor and tune WOT on the street. I was on the pedal probably 15-20 miles into the new motor

 

Race engines like mine don't get broken in. They're also not intended to last 100,000 miles but we build them, fire them up and race them with no break in period.

If your engine is still burning oil after 1000+ miles, there's something wrong with it. The only oil it should be burning is the oil all over the pistons and rings when they were installed in the cylinders. That gets burnt off before the engine reaches operating temperature.

 

I've had an instructor tell me that you should avoid babying a freshly rebuilt engine because the rings won't seat properly at all and will instead glaze the cylinder walls, causing the engine to burn oil for the rest of its life. His advice was to let it run no more than 30 seconds on the first startup just to verify everything worked properly, then take it driving. He even recommended shutting it off at stoplights to avoid idling for the first couple hundred kilometres. To be fair, his advice wasn't very relevant to what we were learning (aircraft maintenance) but he was definitely a mechanically inclined guy that had rebuilt more than a couple SBCs.

 

My motor has 400 miles on it and I have been beating the hell out of it most of its life Mine doesnt smoke either.

 

Mine actually broken in while trying to tune the carb after i dropped in my new motor, cam, head work, and carb. The only way i noticed it was because my motor started to ping and compression went through the roof. haha

Mine only took about 2 hours of varied rpms and some idling on top of the cam break in...I prefer to break the motor in by driving but its a good idea to vary rpms for the first 200 miles. I also dont like to beat the motor till 1000 miles so i dont spin a bearing or screw anything else up.

 

If its going to happen it will happen. Doesnt matter if its soon in the engines life or later. Fire it up and run it. If it breaks then something either was done wrong in the install or just the bad luck of a poor quality part that failed prematurely

 

I broke my 383 in on the way to the track and did 20+ passes.
No smoke/ oil useage but had crankcase pressurisation problems until 1000 miles when suddenly it went away so I can only assume that was when I got proper ring seal ( Hellfire rings / forged pistons)

 

so i should beat on it to break it in?

 

1100 miles is WAYYY too late to be thinking about break-in.
Beat on it! It's not possible to hurt anything at this point.

 

Typical street engine break in procedure

Engine ready to fire up for the first time. Try to get base timing as close as possible before firing up.
Fire up engine and keep it running for about 30 minutes varying the rpms to break in the flat tappet cam. If a roller cam, this procedure isn't necessary.
If you had a flat tappet cam, after the cam break in, change the oil and filter.
Drive normally for 500 miles.
Change the oil and filter.
Drive however you want changing the oil and filter on regular scheduled intervals.

That's it. If the engine was assembled properly, it should last many trouble free miles.

 

alkyiroc, that makes the most sense out of all. Thank you

 

You're dead on the money , I build engines and this is method for which I break them in, I have yet to receive a complaint of early engine failure