As I paid less than $500 for my DCAI that is thermal coated, I can't see a savings incentive. You linked a 7-year old thread to back up your statements...so that doesn't mean much. The fact is that the wye or "Y" pipe leading into the TB causes turbulence by design, whether it came off a stock 6 or a 55K motor. The NW elbow has no restrictions leading into the TB.