Engine mounts can be checked by grabbing the engine and shaking it vigorously in the engine bay.  If you have clanking to any kind of noise, the engine mounts are probably broken.  Broken engine mounts contribute to excessive engine vibration and increased vibration in general when the engine is running.  Fortunately Mazda Competition offers stiffer engine mounts that are made from 40% stiffer rubber.  Mazda Competition part number is FBY1-39-040; two total are need - one for each side.

Mazda Motorsports

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