So how many miles does it take to break in a new engine and has anybody seen any performance increase?

 

The first 500 miles is the break-in period. On my '14 I made sure to be all over the rev range in the first 500 miles, then drive it like I normally did. But I still feel like it took the first track day to real break the car in. With ~3000 miles on it I took it to a road course, where it ate ~1QT of oil in the first 3 sessions. Then in the remaining 5 sessions it didn't use a drop, and hasn't used any oil since (now over 11,000 miles!)

 

Great!! Im at 444 right now,,good you mention the oil to check if often!! Thanks

 

Does the engine get more power after break in?

 

There is no break in period on a modular motor. The day of seating the rings is long gone.

 

For some strange reason on the 5.0, that's a common story. It uses oil at first - in some cases quite a lot. (several threads here - many ran 2 qts low because they foolishly did not check it) But after you finally run it good and hard and good and hot, it quits using oil.

Most info says rings are seated quickly within like 100 miles. But I don't know where the excessive oil usage on the 5.0 would come from if it isn't the rings. I don't know any reports on any engine that valve seals need "seating".

The 4.6L3V wasn't like that. The Manual says mix up the rpm range the first 1000 miles. I quickly worked up to redline (up and out) after the first 100 hundred miles and then played throughout the range - including decel. First oil change at 700 miles, no usage.
<BREAKING-IN YOUR VEHICLE
Your vehicle does not need an extensive break-in. Try not to drive
continuously at the same speed for the first 1,000 miles (1,600 km) of
new vehicle operation. Vary your speed frequently in order to give the
moving parts a chance to break in.
Drive your new vehicle at least 1,000 miles (1,600 km) before towing a
trailer. For more detailed information about towing a trailer, refer to
Trailer towing in the Tires, Wheels and Loading chapter.
Do not add friction modifier compounds or special break-in oils since
these additives may prevent piston ring seating.>

Now with 31k, only used 1/2 qt at 5600 miles (with oil sep).

 

I checked my oil at 100 mi at was about 1/2 qt down. I then worked the engine very good between 100 and 500 miles. Hasn't used a drop since. I worked for a reputable Corvette race car builder during the early mid 2000's and we would get engines from our build room, install in car, heat cycle a few times on chassis dyno, make sure no leaks and then wide open throttle a ton of times full power.

They always ran beautiful and never an issue. Was told they will seat the rings within 20 min of hard running. If they don't seat right away, they then have a hard time seating over time and will use oil until then. We used conventional Kendall 10w40 for break in (LSX & LT5 DOHC engines), and then Redline 10w40 at track.

 

This^^^

 

Drive it like you will normally drive it. For me, that's high rpm in the first three gears lol, I got sideways in front of my dealership immediately after finishing the paperwork. Ok ok it's s roush car in front of a roush dealership so that's kinda expected ha!

 

Yes ! There is a break in period.. According to page 5 of your owners manual, although an extensive break in period is not required, it does clearly state not to drive your vehicle constantly at the same speed during the first 1000 miles..

Page 5 also clearly states, do not add any type of friction modifier compounds or special break-in oils since
these additives may prevent piston ring seating..

 

Thats good,my speed varies so much anyways so no issue there,when would you do the first oil change?

 

The owners manual doesn't mention anything about that ! From my understanding, it just states to change the oil every 3000 miles or every 3 months

 

I didn't get much of a break in. My car had to be transported 183 miles from the original dealer to my dealer. Based on google maps, the distance comes to 185 miles. So he must have found a shortcut to shave some miles off and it must have had close to no miles on it when he started. I hope he treated it gently!!!

 

Many feel better about changing the factory oil within the first 1000 miles in case of any particles from assembly. You know, bearing material, filings, gasket shavings, cigarette butts, beer tabs...

The filter should catch it but as a precaution you will read many change it out. I did at 700mi. on Bullitt and always have on a new engine before 1k hits the clock.

 

Now you tell me Charlie lol. Sure wish I'd known this over 9 years ago when purchasing my first S-197, which was a factory ordered 2005 GT

 

Would have loved to cut that first filter open. lol

 

LOL, definitely don't want any cigarette butts or beer tabs in my engine!

 

On the 2015's it actually doesn't say to change every 3K miles. It says to change it when the Intelligent Oil Life Monitor tells you too, which can be between 3K (for towing) and 10K miles (normal driving)

 

My 15 was on the Dyno at 102 miles. And has been back to the dyno twice since then. It has 390 miles on it now. About 90-110 miles are dyno time.

 

Can just imagine all those beer tabs and cigarette butts that i must had missed