Originally Posted by kennybobby
The whole concept of EGR has never made much sense to me--pollute the charge air to weaken the power...oh yeah that's a great idea...?
The whole idea is to reduce pumping losses. Reducing max power output by any method means that you need to open the throttle farther to maintain the same power output. This reduces pumping losses and increases efficiency. Since engines are so massively over sized for cruising, anything to aid this is a good thing. We do this by many different methods:
vvt and other valvetrain tricks like vtec
probably more I can't think up right now