Cam Rocker Ratio Choice

67autocross said

Say I’m building a SBM (which is always the case) with a solid lifter cam and want around 600 lift at the valve…what are the pros/cons of using a smaller cam with a higher rocker arm ratio say 1.6 or 1.7 VS using a cam with more lift and a 1.5 rocker arm ratio…what is the consensus on the best way to get the lift….again solid lifter cam rollers need not apply

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Here's David Vizards take on choosing a cam has some about rocker ratio.

Engine Camshaft Basics - Popular Hot Rodding Magazine

It really depends on the situation for most builds 1.5-1.6 are fine, Bore cid valves (head flow) has a lot to do with it eg. take 360 4" bore with 2.02 valves vs 402 4" bore with 2.02 valves, 360 has a better valve to cid ratio and is gonna a easier time filling the cylinders 402 is under valved look what most big blocks run for valves 2.02 is extremely small Higher ratios will help. Other things make sure cam will work the higher ratio you'll need more valve spring to control the valvetrain etc..