Have you tried tightening the lash? What Pushrod size? Do you have titanium valves? I am not sure of the value of Ti valves at your rpm, but would think it would take a lot of stress out of the combo as you get more radical on valve action and lift.
Haven't messed with lash on these 1.6 rockers. Only ran it yesterday with this combo of rockers.
Did run lash the same as the 1.5s.. But didn't want to get to tight cause it is close to the coil bind numbers.
I have 3/8ths 120 wall manton pushrods and stainless valves.
