I believe the vantec is about 80mm long by about 65mm wide, in which case an 80mm fan would go great on one of these, I recomend the 47cfm ys-tech, you will need a fan grill for it as well, to attach it you should screw the grill to the heat sink with it lined up on 3 of the sides so it will only overhang one side slightly, then attach the fan to this, I have an 80mm fan on my FOP which isn't quite as big as the vantec and it cools as well as the delta but isn't as high pitched (I have a lot of other case fans so the volume didn't matter it was pitch) you could also try making your own shroud from a biscuit tin for it to focus the air at the heat sink but this doesn't lower the temp that much, on my fop it only made about a 1oC differance but was louder, running the fan at 17v had more effect and was still only the same volume