High revvers

[dbtk2]

All the rocker arms do is multiply the lift of the cam to open the valve that far. So if the cam itself has .200" lobe lift, then with 1.5 rockers the valve will have .300" lift. Higher ratio rockers will make the ramp rate quicker so the valves will open and close faster with the same cam, so you are kind of adding duration as well. So by using different ratio rocker arms on the intake and exhaust you can kinda fine tune the cam to get it where you want. I was considering doing 1.6's on my intake and 1.52's on my exhaust with my 260 cam to get the lift close to equal, but then decided to just run 1.6's on both. (although I haven't installed them yet) Its very common to use different ratio rocker arms.

[oil pan 4]

I got those rockers for the same reason as a lot of the parts I get.
It was the right part (or close enough) at the right time at the right price.
The speed shop had them, they had been sitting there for a long time and they didn't want them any more so I offerend them some $$$.
I have the porting I did to my heads on my cardomain site .

[614streets]

272, sbc z28 valvesprings with dampers , I forget the seat pressure off hand but its matched , no cups , 1.6 roller tips, stock rods, paw lifters , 1 1/2 " primary lone tube headers , 8 lbs of boost , ss valves / swirl polished , 670 cfm throttle body etc. It revs cleanly to 6500 - 7000 but wont know the actual redline until its dyno tuned.