How much more lift from increased rocker ratio

[SicSE]

This is hypothetical, let's not argue about specs, just someone chime in with the applicable calculations.

How much would valve lift increase by upping the rocker arm ratio from 1.8 to 2, given valve lift of 9.8mm & lobe lift of 4.8mm?

 

[Ray]

did you read this thread, yet?

 

[SicSE]

did you read this thread, yet?

Yep... a long time ago, a few times over... and again today since I had faith in you. :laugh: Unfortunately though, the calculations I seek are not in that thread.

 

[striker2]

valve lift = lobe lift * rocker ratio. how hard is that? :shrug:

4.8*1.8=8.64 valve lift
4.8*2.0=9.6 valve lift

9.8/1.8=5.444 lobe lift
9.8/2.0=4.9 lobe lift

9.8/4.8=2.04 rocker ratio

 

[SicSE]

9.8/4.8=2.04 rocker ratio

This is what was throwing me off... because the specs for the Contour are listed as 9.8, 4.8, 1.8:1. I should know better by now than to put all faith in listed specs. :blackeye: