Today’s candidates:
Flat deck spoiler with 45 degree rear up-kick.
Flat deck spoiler with 20 degree rear up-kick.
20 degree deck spoiler, rising a total of 3” at the rear edge.
—The Shootout———
First off, my bad for the camera quality. It was hand-numbingly cold today and for the most part I just recorded inside the car. All I have at hand is my phone and a homemade stand that sits in the passenger footwell. Crappy roads all over.
The flat deck spoiler with the 45 degree up-kick produced similar airflow to everything else I’ve tried. It really sent that long red tuft into the air!
The 20 degree up-kick had about the same flow, although the red tuft had dropped a bit.
The fully-angled 20 degree deck spoiler seemed to hold the longer tuft at a similar height. Airflow down the rear glass didn’t look any different.
For contrast, I tested my deck spoiler on its own. The red tuft had come in closer, but is still hovering 2-3” over the rear. The rear glass airflow looked…The same.
For the sake of “why not?”, I ripped everything off and tested the stock trunk lid. The red tuft would alternate between touching the rear edge of the trunk lid and floating 1” above. Once again, the rear window had similar flow.
As a last note, here’s a side shot I got of the car with the 45 degree up-kick in place. If you look closely you will see the red tuft flying with the birds. Wow! That’s not even close the trunk. Interesting.
————Conclusion?——-
Hmm…Not sure. Nothing seemed to have really affected the airflow on the rear windshield. That red tuft is the only real deviation, though I’m not wholly sure what it means. From what I’ve seen/read, that tuft should be much closer to the trunk lid. If that’s correct, then the stock trunk performed best.
However, I am not measuring or testing pressures. It’s very possible that these shapes and extensions can make varying differences in pressure on this vehicle. I really should build a magnehelic testing setup. I could try and use some water/dust testing as well.
So…More to learn.