When is an engine fully run in? As in max power/economy?

[Logic]

I know the break in period for most engines is around 1000 km or 600 miles, but IIRC it takes a bit more mileage than that before the engine is at it best.
At it's most optimal power or economy, depending on your foot.

I see that in Canada cars are 'run in' for 6000 km before fuel economy testing..?
https://en.wikipedia.org/wiki/Fuel_e...in_automobiles

"I’ve been told by factory trained technicians to not expect advertised specifications until at least 10,000-15,000 miles"
https://www.reddit.com/r/askcarguys/...umulate_miles/

???

[freebeard]

New tires at 500 miles, so :shrug:

Is that when the boron additive goes in?

[Ecky]

Anecdotally, Insights seem to do their best after at least 50,000 miles. 1-2% differences are easier to see in them when they're getting the better part of 100mpg.

[Logic]

Originally Posted by Ecky

Anecdotally, Insights seem to do their best after at least 50,000 miles. 1-2% differences are easier to see in them when they're getting the better part of 100mpg.

Thx Echy

Wow! At least 50 000 miles is way more than I expected!
What's your regimen for oils and filters?

[Logic]

Originally Posted by freebeard

New tires at 500 miles, so :shrug:

Is that when the boron additive goes in?

Let's keep this thread Boron free shall we freebeard. You know what will happen otherwise.