I guess the deciding factors were familiarity and that Calvert racing offers a leaf spring upgrade for bigger horsepower. I know VAS has incredible 60 foot times, but Calvert Racing is doing that and putting cars in the 6's. My goal is 11-1200HP. No way to make that stick with stock leafs....we have a 68 Camaro thats dealing with stock springs and the inconsistencies. Its just my opinion though! I know everyone has their preferred way of going fast, but I've never built anything this fast so I'm just watching and seeing what works and what doesn't, forming an opinion and plan, and then swing for the fence......