From the first moment I saw this Y-Pipe design as part of the original kit it never sat right with me. Always had suspicions of issues with inconsistent readings. Now I've already ordered TopgunZ's kit but thought in the meantime set out to prove just how inefficient the Y-Pipe really is.

My suspicions came from the idea that even with the recommended air deflection plate Stillen insist you use (redundant for me as I had the FrozenBoost Heat Exchanger which completely blocked my front bar opening thus preventing the problem the deflection plate resolves) there simply isn't enough time/length between air entering the Pod Filter to settle into a steady flow before hitting the MAFs. This is a problem for those who tried doing a Hybrid MAF/MAP tune since driveability suffers as a result.

Prior to working with Seb, a previous Tuner decided to bridge my MAFs to get around this. But long story short, didn't really work out too well, and my MAFs were maxing out at about 4000 RPM.

So I undid the bridge, got Seb to eTune, and picked up some generic 2.5" pipes & couplers to extend the distance between Pod & MAF and the results were pretty promising, see attached. Both done @ idle. Gave accelerator a small stab in the second.

This was done pretty much for sh*ts & giggles, and utterly redundant once the A2A kit finally arrives. Just makes me question all the more who the hell oversaw the design of this kit and who approved it in the end at Stillen.

TL: DR - Hated Y-Pipe from beginning because path of air too short between Pod & MAF. Bought some cheap 2.5" pipes & couplers to extend that path. Logs showed a marked improvement.

...not even going to get started on that atrocity of a silicone coupler piece at the SC itself...