Best way to determine its efficiency is to do a third gear pull from ~2500 to redline logging the Charge air temps, RPM, and boost levels. then see the difference of the Charge temperatures from the beginning of the pull until you hit redline or highest RPM. My j-line was 10-11 degrees usually, and My DHM Race is typically less than 4 degree difference. I'd bet this thing is as efficient if not more so than the J-line.