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aerohead · 08-28-2010, 04:03 PM

3d,if I had to guess what happened,I'd say the the Protege originally had the typical notch-back downwash which would have allowed the sepatated flow from the roof to re-attach at the back of the trunklid.
The Kamm-back is causing an 'overshoot' condition,directing the air out into 'space' where it cannot re-attach,and consequently increasing the wake size and lowering the base-pressure.Both bad.
I like what you did with the plex.I would either extend it further back,or extend the back of the trunklid back and up at a 30-degree angle ( no steeper! ) with a spoiler to give the air a place for re-attachment.
Some cardboard and duct tape should make a showing on your coastdown.

08-28-2010, 04:03 PM	#16 (permalink)
aerohead Master EcoModder Join Date: Jan 2008 Location: Sanger,Texas,U.S.A. Posts: 16,306 Thanks: 24,436 Thanked 7,384 Times in 4,782 Posts	lost you re-attachment 3d,if I had to guess what happened,I'd say the the Protege originally had the typical notch-back downwash which would have allowed the sepatated flow from the roof to re-attach at the back of the trunklid. The Kamm-back is causing an 'overshoot' condition,directing the air out into 'space' where it cannot re-attach,and consequently increasing the wake size and lowering the base-pressure.Both bad. I like what you did with the plex.I would either extend it further back,or extend the back of the trunklid back and up at a 30-degree angle ( no steeper! ) with a spoiler to give the air a place for re-attachment. Some cardboard and duct tape should make a showing on your coastdown.