5/16 or 3/8 pushrods on 241s
Given that, flex does come into play. The pushrod can still flex without reaching its first harmonic. It is possible to have a pushrod that has its first harmonic above the range that would be excited within the valve train, but the flex would cause issues with valve bounce. Therefore, the stiffest pushrod you can fit in without having valve float is the better solution. I wasn't sure the double taper would fit when I bought them but rolled the dice and checked them out once I had them in hand. They cleaned up my upper RPM quite a bit. I wasn't looking for a hp increase, rather better valve train stability to prevent issues with valve bounce which will wipe out cam lobes and lifters.
Thank-you for explaining your thoughts...explanation of the specific pushrod issues that were being addressed in the calculations.

