Quackie the duck was helping me flow a set of heads today. He understands a little more about air flow than I do. It was nice that he took the time to explain some of the things we saw.
There are vacuums more than capable of flowing a set of heads at every Home Depot. All you have to do is get on the roof and get the one that moves those shuttle canisters from the cash register to the cash room. You just need to make sure you have enough power at home to run it.