>>>*I did this one at my shop. I had a 5 H/P unit, with about a 40 gallon tank. To run the valve seat grinder, air buffing tools, air float boring tables, die grinders, etc, it was impossible.

So I unhooked the 5 H/P and installed a 10 H/P with a 100 gallon tank, that still was not enough, only two men could work at any one time with air tools.

Then I installed a valve to the 2nd tank, running off just the 10 H/P unit and that works.

Volume is the key, no savings on power of course but the savings in manpower and production time was a lot....*EB

*Beats the he** outa me!....*LOL**...