not sure why more don't follow gazim and find something from a scrap yard, there's a lot of "brand name" ones available, my local yard had a 50' long wall full of all sizes, all pre-tested, guaranteed and less than 1/2 new price
Bill
Because I needed something that I knew would work (I mean fitment wise), would cover as much of the rad as possible, and could push as many CFM as possible. I also didn't want something with a factory shroud, as it would obstruct airflow in my application. As cooling is a big concern for my application (and any rod), this isn't an area where I cheap out.