This ring gear has a 10 1/8" ID to fit the common Ford 2.0L SOHC Pinto flywheel. Some later model FF1600s also use this ring gear (the SCCA-legal JAE flywheel for FF1600 takes this ring gear).
This ring gear now has a special double-chamfer tooth design to work with both Tilton (pre-engaged) and Lucas (inertia) starters. The ring gear should be installed with the chamfer on the leading side of the teeth, so that the starter teeth make contact with the flat side. That means the teeth on the starter side (the right side of FF1600 and 2.0L SOHC Pinto engines) should have the flat side of the teeth facing down (towards the starter).
Note: Some recent British cars use a 10 1/8" ring gear with 132 teeth. This ring gear will not replace the 132 tooth gear without changing the starter.
