Originally Posted by MBDiagMan

How long is a rope? That's a question that is framed in the same way as the question in the original post.

A rope might be five feet long if used for a piggin' string, or 35 feet long if used for a lariat. An engine might not last until it's warmed up good, or it might go a million miles. It's almost totally determined by two things; how it's maintained and how it's driven.

Today's engines regardless of brand or size or configuration are ALL long lived. The reason?????...... Electronic Fuel Injection! There are several other less important factors that improve todays engine life, but EFI is BY FAR the most dramatic.

With EFI, you don't have a choke on a carburetor that is mostly not working properly or misused. Even if the choke is working properly, you are still dribbling raw fuel droplets down the cylinder walls during cold starts washing all the oil off the cylinder walls.

Additionally, EFI under most all driving conditions, while in closed loop mode, maintains a constant air/fuel ratio. Thanks to knock sensors, the system also prevents preignition which is a SERIOUS engine destroyer.

Add to EFI, the less dramatic of todays improvements including better lubricants, more precise parts machining and improved cylinder/piston/ring material packages, among a few other things and you have engines with the capability to last forever if maintained properly.

BTW, the highest miles I've ever put on an engine is 533K miles. If you're curious, it is a Mercedes diesel. The reason for the long life of diesel engines is a whole different story.