A rough prediction for your scrub pattern: if you have mid-lift and correct geometry, a .400" lift cam will sweep only .010" across the stem tip. Anything more means something is wrong.
If the pushrod is too long, the rocker will always be angled too far down in all positions, the scrub path will begin at .00" lift too far from the rocker shaft, stop traveling across the stem tip and reverse before 50% lift is reached, and will return to a full-open position closer to the shaft.
