Roller Rockers Geometry
The ones I posted a picture of are part number 1322-16 and are called "Pro Magnum Rocker Arms". I see the 1420-16 listed in Comps on line catalog and they are "Magnum Rocker Arms", not "Pro Magnum" like the ones I have:
http://www.compcams.com/information/Products/RockerArms/MagnumRoller.asp
I don't see the 1420-16 listed on Summit but if you search they still sell replacement shafts for them:
http://store.summitracing.com/partdetail.asp?autofilter=1&part=CCA-1079-2&N=700+115&autoview=sku
Print