Roller Rockers 1.5 vs 1.6

DentalDart said

How do you decide on which ratio to get?

I didnt get any when I purchased my aluminum heads but now SM has all the SS rockers in stock ( well kinda...) so since they haven't had any in 7 months I think I may pick up a set... I kinda want 1.6 for a little "extra" lift from my cam but worry about valves hitting pistons?

Build...
30 over 340, pistons all around .012 out of the block
Xe268h camshaft
SM CNC fully assembled heads (pictured)

I know I know buy the expensive ones that are "better..."

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I recommend watching the David Vizard youtube video on LCA selection. Part of his Powertec 10 series. Ep 17 and Ep18 cover rocker arms and discusses when a higher ratio rocker is likely to improve torque and in which situation it will likely reduce torque. Torque is the value we can measure, while power is a value calculated from torque and RPM. LCA is critical to maximise output and needs to be determined using DV's 128 formula;
128 - (cylinder displacement for one cylinder/ intake valve diameter × 0.91).