I seen a build where they went from 1.5 rockers to 1.6 and had same problem.
That's a fast ramp cam the 1.6 might make it to fast to control or need more spring.
Comp Cam did not seem to think there would be a problem. The valve springs are good to .700 lift from what they claim! They knew the complete build including the 1.6 rockers!
