[aerohead]

Using available photographs of the ECOTEC LSR car, I modified the technical drawing, lowering the car, and adding the SCTA-spec rear spoiler with 'spill' plates ( as they refer to capping plates ).
Estimated race car dimensions:
Length- 185.59-inches ( 4714 mm )
Width- 67.91-inches ( 1724.91 mm ) published
Height- 53.21-inches ( 1351.53 mm )
Body height- 49.116-inches ( 1247.54 mm )
Forebody- 54.22% of total length
Aft-body - 45.77%
Ground clearance- 1.00-inch ( 25.4 mm )
Verjungungsverhaltnis- 1.7296
L/H- 3.48787
L/h- 3.7786
L/W- 2.7328
( Long-tail length )- 261.42-inches ( 6640 mm )
L/ square-root of Af = 3.2329
Estimated coefficient of aerodynamic drag- 0.21
Estimated frontal projected area- 22.885-sq-ft ( 2.126 meters-squared )
Estimated CdA- 4.8058 sq-ft ( 0.4464 meters-squared )
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*The OEM Cobalt backlight base slant angle is 19-degrees
*The deck relaxes the backlight-to- trailing edge exit angle to 12-degrees, intercepting the 2013 template contour.
*Addition of the high-mount spoiler relaxes the backlight-to-trailing edge exit angle to 7.3-degrees, with the implication for direct downforce.
* Deleting the high-mount spoiler, and extending the decklid 10-inches, intercepts the original, 'slower' template, which also matches the 1981 VW-Flow Body contour ( Cd 0.14 ) and 2019 GAC ENO. 146 contour ( Cd 0.146 )