Here’s two pennies or less…..You have -1 heads that you will be using, right?….so on their best days you know the limits. If you were building moderate inches, say 470 or less - I would lean towards the low deck and lighten stuff up for RPM. (eats parts and requires more frequent maintenance)

You want 540, correct? Ditch the low block, build a RB in a 4.375 x 4.500 combo and focus on torque, if the car is set up accordingly (converter/gearing) It will last longer, be more reliable and will perform as good or better than the low deck combo……

The 850 HP goal is relevant, its when it makes it and for how long that shows up on the ET slip.