With the inspiration of the Cheaparral car fresh in my mind I set to work...
I calculated that with a large enough manifold that only a small pressure differential was needed to generate huge quantities of downforce. The trick was to find a fan that was capable of generating that differential. Most air moving fans for buildings only create a differential of 1 inch of water (about 0.036 psi). I figured I needed about 10 times that much.
Thankfully there is govliquidation.com. I found a few fans that were close in performance, but finally ended up with a lot of 15 fans from an 8" mobile howitzer.
After spending several times the purchase price on shipping from Ohio I have them in hand. They are monsters. The opening is 24" and they weigh about 90 lbs. each. The body is .5" thick cast aluminum.
Now we just need a car to put it in.
