I read the specs where a Poulan 200-MPH Gas Blower/Vacuum has 25cc, 2-cycle gas-powered engine and 200mph and 430cfm.
450 CFM or so seemed to make enough pressure to create a bubble from the leaks by a good leaf blower.
I'm going to step this up a bit and buy a Portable ventilator and hose and build a custom internal adapter similar to the Sealtech mount and run it. I figure it will cost me about $125 but it will pay for itself once I find the leak as a local shop wanted 2-4 hours @ $120 an hour with a 2 hour minimum. I'd rather run this from the inside than all the contraptions I've seen hooked up with leaf blowers.
http://www.harborfreight.com/8-inch-portable-ventilator-97762.html
This portable ventilator airs out rooms, circulates air or dries wet areas with a powerful air output from 1400 to 1574 CFM. Perfect for dry wall, painting, reglazing, resurfacing, auto body work, welding or any area that needs clean air fast. Features include a two-speed motor, an ergonomic handle for effortless transport and an aluminum blade and steel housing construction for long lasting performance.
•Ergonomic handle for effortless carrying
•Four rubber feet for secure footing on any surface
•High speed free air 1575 CFM
•Low speed free air 1400 CFM