You guys remember those cars of post '72 a lot differently than I do. The '73's had miles of vacuum lines, with all kinds of pneumatic switches to do weird things trying to control emissions while increasing efficiency; the '74's were worse and they kept it up for about ten years. EGR systems were a really neat idea, weren't they? Using exhaust gas to slow down the flame path in the cylinders to prevent knock - what a great idea! And as bad as they were you couldn't change things without violating Federal rules, with fines in five figures for shops that knowingly defeated the OEM package. Yeah, it was a grand time in US automotive history - NOT.