Breaking in rebuilded engine

[Fii]

Ivan141 Wrote:Just trying to get another myth out of this world..you dont need to "wear-in" your bearings on car engines. In fact you can throw your bearings away if there is any wear on them. The wear-in period is meant to seat he pistonrings in the freshly honed cilinder. This takes some time and how long and how gently you do this is also a subject of debate but I dont want to go into that matter.

I completely agree with you about the bearings. And regarding the piston rings, the best way to seat the rings is to make them push hard against the cylinder walls, and the only way to do this is by using high cylinder pressure, and that means - floor it. Since first few times this will generate very high heat due to the friction, it is not recommended to do this for long - so floor it and get it revving up to the redline, and then completely lift off to allow the vacuum to suck out the metal shavings from the cylinders, and for rings to cool down. Drive with 2k rpm for a while and then floor it again.