Fits all 429-460 Ford engines.
This Powerforce® 6.7 inch harmonic balance features two keyways, a 1/4 inch and a 3/16 inch.
The 1/4 inch keyway will allow the balancer to install correctly on a factory-production crank so that the pointer in a '10 o'clock' position will line up at 0 degrees top center mark on the damper.
The 3/16 inch keyway is used with Ford Racing crankshafts (please read all directions that are included, before installing).
