Been very busy with work since racing in Sydney,Stanley wrote:What's doing DB......been quiet at Reedy Creek
but found some time at nights, to work on some improvements.
With some discussions with Roger Crawford at Heads Up performance,
and his valve train analysis program,
the momentum of the pushrods was out stripping the valve spring tension by 7200 to 7400rpm. (800lbs).
So I have reduced the mass slightly, without sacrificing the desired stiffness,
and am looking at making an improved rocker arm to reduce the flex.
I tried a lighter pushrod, made from 3/4" 7075 aluminium, but lift loss was a further .010".
While the rocker arms were not at fault for the failures,
(Mr Crawford uses these up to 11000 rpm and nearly 1" of lift,),
there is some flex within the arm as seen from the loss of lift from light "checking springs" to the actual race springs.
I have made one of each as prototypes,
and will do a production run of one set, once the clearances are worked out on the engine.
Here is an original arm, set on the jig as a guide, to curve the tops of the new ones.
