Header design, need help filling in the blanks

[noid]

Trying to fill this out:

http://www.wallaceracing.com/header_length.php

Stroke: (Inches): 2.9527"
Bore: (Inches): 3.3070"
Number of Cylinders: 6
Exhaust Valve Diameter: (Inches): 1.4173"
Exhaust Valve Opening Point: (Degrees )
Exhaust Valve Duration: (Advertised) 128
Exhaust Valve Centerline: (Degrees)
Peak Power RPM: 5800 rpm
Volumetric Efficiency:

Stroke and Bore and Peak power RPM and valve diameter is taken from here:

http://e30world.com/specifications/BMW-E30-specs-table

Exhaust valve duration is 'assumed' from taking the formula from here:

http://www.hipermath.com/engines/exhaust_valve_duration

(exhaust cam degrees = exhaust valve duration/2)

Anyone know the rest?