Rich at wot is generally considered 4 stroking ... But ill read the article again, and dont get your back up im not knoking it , just doing what people do on forums and that is offer personal experience.

ok read it again.. its different to the one i read earlier..

The article makes great sense and is the best way to run in a race engine by a sponsored driver. This will cause the engine to get to a proper sleeve and piston fit within a litre , thats convenient for someone who are sponsored. you get to the track on the practise day, you open the new motor you were given , pop it in and you start to get it run in quickly so you can get max power out of it asap.

Rodys comments make sense and are pretty close to what i do for break in.

However...

if you are a non sponsored driver and you want to get 2 years and close to 50 litres out of an engine then you need to run it in hot and on the road. using the word heat cycling for the rich on box method is a mis noma , its not considered getting hot sitting rich for many tanks at 45 deg c, thats not hot , you can hold the head still.. .. for example.. Thats not any ones fault , ive never heard rich on the box called heat cycling. My definition of heat cycling is to get the engine up over 100 deg c on the first tank with alfoil on the head Getting it up to HEAT, this is not achieved by leaning the engine but rather driving it so the load gets heat into it... , and once you get between 500 ml and 1 litre you are ready for race tune, the engine will take much longer to break in but is still usable till you get to the 4 or 5 litre mark. then it will start to loosten up. You will have like new pinch right up to the 20 litre mark this way. It may not be your preferred method but its designed to get the most use out of a motor.

Wether you bring the tolerances to fit sooner in WOT method or later in heat method they end up getting to the same place eventually, its just the heat method takes much longer, and some would consider that a hinderance , others would welcome it

My addage is to have a motor last as long as possible, so in the end its horses for corses..

: )