It's all a matter of which water pump you have. Over the years, anything could be on there. The short shaft water pumps were used into the early 70s like 71 and possibly 72. There is no difference in the 67-71 3 bolt balancer and the 72 and up 4 bolt in regards to how far out the grooves are from the block other than the bolt holes and the way it mounts to the balancer. The 3 bolt just appears to be out further because it's longer due to it mounting to inside the balancer where as the 4 bolt style bolts on the face of the balancer. The groves for the belts line up in the exact same place. So knowing that, the only pulley that that has to change depending on the style water pump you are running (short shaft or long shaft) is the water pump pulley itself. I have both styles in billet aluminum as well as the other pulleys if needed. Thanks Nick Alfano Performance 4849-76 st. Kenosha, WI. 53142 262-308-1302 262-942-8271 after 6pm central and weekends Like us on Facebook at https://www.facebook.com/#!/AlfanoPerformance www.alfanoperformance.com -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://list.amc-list.com/pipermail/amc-list-amc-list.com/attachments/20140818/7e5b1148/attachment.htm> _______________________________________________ AMC-list mailing list AMC-list@xxxxxxxxxxxxxxxxx http://list.amc-list.com/listinfo.cgi/amc-list-amc-list.com