They named it what it is. It injects cold air into the exiting exhaust charge to reduce the amount of dissociation of Carbon Dioxide into Carbon Monoxide by reducing the temperature. The EGR valve took over this duty after the reduction of compression ratio didn't do it all in 1971 & '72.
The chamber shape change in 1967 (061 heads) allowed the motors to reduce their "smog" limits in 1968 when all of the heads were switched over to the "open" chamber design. This was combined with a reduction in dynamic compression which also reduced the combustion pressure at lower RPM, further reducing the formation of "smog" gasses.
Glad to hear you're still moving it forward, Brett. I'm busier than ever with the new company, but every once in a while I like to help out if I can.
