Held in place

This tidbit about Ford’s new one-liter three-cylinder EcoBoost engine, as fitted to the Fiesta, almost rated an Entirely Too Cool:

Vibration is inherent in three cylinder engines — an odd number of cylinders means there are no “equal but opposite” actions happening across the engine block to calm things down. Left to their own devices, triples tend to move around on their mounts and often make booming resonances. OEMs generally respond by adding counterrotating balance shafts. This minimizes vibration at the expense of fuel economy and power output, which isn’t much of a sales pitch.

Ford chose a different path. As seen in the video, fore-and-aft motion was dealt with by intentionally unbalancing the flywheel and accessory pulley. The increased lateral motion was then handled via careful tuning of the engine mounts and their placement. They aren’t active mounts like some publications have reported, but they generally do the job.

From my own experience with active mounts, I can testify that (1) they do work, and well, and (2) you don’t want to be the one writing the check when (not “if”) one fails. If Ford has actually come up with a standard mount that can match the actives’ performance level, they’ve pulled off a decently sized engineering coup.





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