Max Power 74 Report post Posted August 28, 2014 I believe Ford used three bolt harmonics in early 69, but switched to 4 bolt mid year. Rather than spend hundreds on a 3 bolt pulley, I would just get an aftermarket zero balance damper and switch to the more common 4 bolt affair. Quote Share this post Link to post Share on other sites
Guillaume69 150 Report post Posted August 30, 2014 I am not sure. My car is a late production, built in July 69, with last VIN digits 222550. It has the 70 bolt on windows in it, so definitely built in the last quarter. Still has a 3 bolts damper. $50 bucks for a 3 bolts / single groove crank pulley is a hell of a good deal, IMO. The few I saw on eBay were more around $200... Quote Share this post Link to post Share on other sites
