Vacuums that run from a compressor use a venturi. These create high vacuum, but very low flow rates. In order to work well, all leaks in the system need to be eliminated.
Typically, when using a spoilboard, you'd use a high flow vacuum pump, which typically has lower vacuum. The reason is that vacuum will suck right through mdf, and wood as well to a lesser extent. The high flow rates allow parts to be sucked down to the spoilboard by the vacuum sucking through the spoilboard.
With your low flow system, all the vacuum would be lost through the edges and exposed surfaces of the spoilboard.
The best option for that type of system would be to make dedicated vacuum pods from a non porous material, like acrylic. If it has a grid routed in it, gaskets can be configured to fit your parts. With a very good leak proof seal, a pod system can get tremendous holding power. Keep in mind, though, that holding power is proportional to part size. The bigger the part, the more power you'll have. Small parts can be extremely difficult, if not impossible to hold with vacuum.
See the following links for the type of fixtures that you should use with your system.
Vacuum Clamping (Vacuum Hold-Down Jig)
How to Build a Vacuum Clamping Matrix