For a back of the envelope calculation,if your mpg was 17.53,and went up to 18.93,that's a 7.98% mpg improvement.That would suggest about a 15.97% drag reduction.If starting at Cd 0.41,your 'Wedge" would put you in the neighborhood of Cd 0.344.
Not too shabby for a single mod! And you probably saved at least 300 man-hours in fabrication time versus an 'ideal' cap.
I like it! Thanks for doing it and sharing the data.
