I always check the rocker ratio on any engine I build. I keep a block close by for testing purposes only. The Mopar factory mechanical '273' rockers are very strong and durable, I find them in the 1.45 range. Best being 1.51 and worst 1.41 . Also with the pushrod and lifter not being 'in-plane' with each other loses .10 of lobe lift . Very easy to calculate actual lift at the valve with lash. Subtract .10 from the lobe lift from the cam card and multiply by rocker ratio and subtract lash puts actual lift within .001-.002 . Works for hyd. cams too, you have no lash to subtract .
