Arouse the DAMPFHAMMER!
That's an awesome work Scider. I really appreciate your measurement!
The setting of the centerline is mainly driven by mean VE and peak VE for each cam and the application. Of course it is also depended on the cam duration and profile shape. The lower the speed, the less gas dynamic support comes from impulse of the gas column, it's more related on the pressure swing. This is the main driver for VE and therefore the camshaft centerline. At higher speeds, even with higher duration of valve opening, the gas impulse and the the more retarded pressure wave helps to keep the air inside when piston is already moving up.It's somewhat interesting to see the offset between the lobe centers for high and low speed...This is probably designed around the factory VTEC switching point so the cam phaser doesn't have to move.
I know it exactly from TODA A3: low speed cam exhaust centerline is advanced by 4° compared to high speed cam. Centerlines of low speed and high speed are almost the same, as it is just a VTC work thing. A note, the low speed intake camshaftes have different centerlines by 2.5° difference, to start a sort of swirl for an faster combustion when the intake gas speed is low (part load - emission game). TODA overtakes that from the OEM camshafts.It makes me curious what aftermarket manufacturers are doing with their cam designs, and what design philosophy they use for the low speed cam profiles.