Unfortunately that doesn't do anything.
When 034 Motorsports started testing during their development they did the snow catcher delete and a panel filter, gained 1whp.
APRs intake has been independently tested and gained 12whp. Unfortunately Uni's intake wasn't included in that test.
I use the K&N drop in for slightly improved throttle response, that's it. While they don't filter as good as OEM filters, as many will note, they offer lower initial flow restriction. At the high end, this doesn't yield much, if any difference in peak HP, as you have noted. I just swapped back to the fat stock paper filter for a day or two to clean my K&N, and then switched back again. I can certainly feel the difference in throttle response. Admittedly, it is subtle, but still noticeable enough for me to stay with the K&N. Also, theoretically, since the engine requires slightly less power to overcome the the initial airflow when taking off from a stop, this could yield a very minor fuel economy increase. We are likely talking very miniscule here and probably not even measurable.
So i spent all morning researching intakes, and the R600 might be my next purchase.
Seems like both the Uni and APR require coolant reroute and breather filters for secondary air injection?
Agreed. That's the one I would get if I was going to lay the $$$ money down. It's like a $50 per HP investment, plus you gain some nice modest intake sounds along with the integrated SAI bung. This keeps the SAI noise to a minimum on startup like the OEM unit. I didn't like the open breather I tried with the open filter a couple years ago. They increased the SAI startup noise two-fold in my experience. And, with the R600, you get the OEM look and feel that I also like.
I noticed ECS has dyno charts for their inhouse open and closed intake systems. The open intake with a nice heat shield yields 5HP and the closed intake system with front air duct yields 10 HP (on APR stage 1 GTI). This is in line with what you are saying as well. Like someone else stated...you could not pay me to use another open element filter, especially one without an effective heat shield. They look and sound great, but they not as good for cold air flow as stock and many of them don't provide the same smooth stock-like acceleration "feel".
It is also good to note for all reading this...the more power you make, the more HP a more efficient intake will yield. Those running stock are NOT going to yield that 10 HP like a tuned car will be able to. All dyno charts for intakes that I have seen use stage 1 or stage 2 tunes that require increased airflow.
