Just to be informative. Air Zenith claims the OB2 outputs 3.5 CFM, however it also is only recommended for 5 gallons of air. So you can’t do just one OB2 on a 8.5 gallon tank (unless you want to void your warranty and potentially damage the pump). Viair Dual 480Cs are going to be the most cost effective way to do it. From there consider three/four 480s, two OB2s, or an Oasis XD3000. All of which are pretty much overkill.
495Cs are also excellent pumps. They go to 175 PSI instead of 200 though, so you get a little less air and volume (spl). But two of them would be extremely fast…
