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how did you break in your boss?

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Tucson302 said:
I think most on here waited until after 1000 miles to really run it hard.
That's what I did also. But it says it helps a lot but I don't think I can bring myself to mash the gasbefore over at least 500 miles
The owner's manual actually gives milage until hitting redline, track use, etc. 600 and 1000 miles come to mind respectively. I'll be just over 1000 on my 2013 when I get to Autobahn on June 3rd.
first 100mi were used to learn how to drive manual, after that i just drove normally, exceeding 6500rpm handful of times.
Car burnt 1qrt of oil the first 1000miles, then stopped. Basically, i did not pay extra attention to break-in, so don't be too worried about it.
I literally bounced off the rev limiter pulling off the dealers lot and called it broke in. 8)
My youngest son drove it 2,000 km's from where he lives at speeds aproaching 170 kmh to deliver it for my Birthday. It was definately broke in by the time I got it.
I drove it no differently than I would have normally, which means beating on it mixed with highway cruising. But I didnt redline it until I was over 100 miles.


Performance Fords
so, i was nice for 100 miles then gave a bunch of rides. Every ride saw the redline in first and second. I daily drive now and bounced over 13,000 miles today. This car sees redline at least twice a day...


Right away I did what most have told me a long time ago. On the way home put in 3rd then from 3000ish rpm to 5000ish rpm full throttle, then engine brake back down to 3000 rpm. I do this approx. 10-15 times(helps to seat rings), then drive normal to the everyday driver. My concern to a brand new car (any) is that the oil in the motor has not properly lubricated the internals with that nice black film. This film attaches itself to the moving parts, but it takes some time to build this. The following oil change will not matter because you will not completely remove that film doing oil changes. I was told this theory a long time ago by a friend, he had mentioned he seen recommendation to not do a track day on fresh oil. To allow the oil to turn blackish. This could be hogwash though. It just makes sense to me to allow the fresh oil to cycle some before pounding it.
I had concerns about my track day break in procedure, but with 3600 on the Boss I have experienced no oil burning issues. My normal procedure is 1000 miles, but the Boss just begs to be drive hard!
It's my understanding that you should drive it like you stole it. What you shouldn't do is drive at constant high rpm for a long period of time until you have about 1000 miles on it. Like 140 on the autobahn for an hour.

Grant 302

basic and well known psychic
Forgot to mention one of the more important parts of running the engine up in RPMs is to also let the engine decelerate off-throttle to get maximum vacuum to help seat the rings for travel in both directions. Under vacuum, the crankcase air pushes the rings out while on the intake cycle. WOT engine power cycle keeps the rings seated on the downstroke.

There is *some* science to why engines should be broken in hard.

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