VW Passat VR6 Engine Refurbishment: Optimal Speed, Gear, Oil for Break-in Process

I have a request to answer the question how to reach the engine after a major renovation?
The engine is after:
- Ream the first cut
- new rings
- new main and crank bearings
- planned head
- new seals etc.
Some talk about breaking in hard but somehow I am not convinced. Rather, I am closer to calm running in, but what speed do I drive, what gears, and most importantly what oil?
Apparently it's best to reach the mineral.
Please give me a hint how to do it to do it right.

If it is put together well, nothing bad can happen. There are different schools, I always got the engines after repairs "hard", the point is that the rings (which seal under the influence of pressure in the combustion chamber) adhere best to the cylinder wall. This helps to maintain the level of compression at an appropriate level, reduces the amount of oil entering the combustion chamber, the engine "does not spit" with pneumothorax.

The engines that I repaired and arrived in this way are still running today, and the owners do not have to worry about adding oil.

This is done on mineral oil to speed up the break-in process of the mating elements and because it is cheap. Another advantage is its high density, which gives us a higher value of oil pressure, which is important at the first firing.

If you choose this method, you'll find break-in procedures on the internet.

PS. Remember to position the ring locks correctly.

Break-in is a good method, but traditionally you can pour the oil recommended at the factory and run the engine for 15 minutes, drain the oil and pour it again at ease let the temperature come for some time. Then drain the oil again and pour in the oil and replace the oil filter.
Drive calmly over a long route without overloading by changing the engine speed range.
After approximately 1000-1500 km, the oil and filter should be changed again.
All to remove micro filings after lapping.
Of course, the first start without ignition so that the oil pump fills the lubrication system with oil.

Approach of a good motor driver (engines from his hand experienced the rest of the car):
The oil may be a bit higher in viscosity than recommended - it gives a stronger oil film (greater resistance but also better protection of surfaces that are just matching each other, especially when high temperature is generated). In any case, 0W30 or 5W30 will be risky here. Mineral is probably only recommended because you mix it immediately (you will not use additives in synthetic oils) - you can and a synthetic - with such a short run as it goes to the first oil, it probably does not matter what oil base. After how many km he never said unequivocally, but more or less - several dozen km (or several dozen min. Idling) - the first change. A few hundred km (here without work at idle, normal driving recommended) the second shift, about 2-3 thousand km - the third. After this, in principle, it should already be reached and you can use full power or drive economically, e.g. on the highway at constant speed. Of course, oil and filter to dump.
First start - do not allow the engine to run dry. A pump without oil may not suck it out of the bowl at all, so turning it at start-up speed and if it doesn't help - pouring the system from the top.
Driving - at various speed ranges (also high), but without senseless rippling and excessive loading (a lot of heat is generated during the break-in - just feel it). Emeretic driving is not advisable - it does not affect the rings and valve seats as well as the parts are new or freshly cut.

Do not pour the mineral because if you break the film, it is your job for a dog. It's not 126p that he rode on anything.

Pour oil as it should be. Start the engine and let him work these 10 15 minutes without anything.
Start riding the deli first. The first few kilometers. Literally a couple. Later normally. Change gears higher. Rather use higher than lower turnover.

I follow this rule.
Pour oil as recommended by the car manufacturer to the engine.
start it and let it work for 30 minutes at low speed and control the work and temperature.
Later, driving and do not change gears, e.g. at 2 thousand, because it matches the engine, change normally, but do not use the engine power abruptly, but use the rotational range, maybe not fully, but 3-4 thousand it is calm. I drive for about 250km later, I change the oil, filter. then I drive normally but I don't use max engine power and I don't use jeszce with max speed but I drive dynamically.
after another 300km you can change the oil again with the filter and oil and I drive normally

Art.B wrote:

You write new rings. And the pistons? What manufacturer and what clearance in the cylinder?

Pistons original, oversized, i.e. from the 2.9 VR6 engine, clearance on the cylinder 0.03