These beautifully machined roller rockers are designed just for the direct injected Yanmar engines commonly found in the Pro-Stock diesel class of NQS pulling. These come optimized for the valve hight that the legendary engine builder Carlton Cope used in his Yanmar builds. Some engine building knowledge will be required when using these to set proper rocker arm geometry. We will gladly do it for you if you send us your assembled head. This kit comes with everything needed to install. You will use your factory rocker shaft and spacer springs. This kit replaces the old Harland-Sharp kit that was insanely expensive and had very inconsistent ratios. These are built to take 5/16” ball end pushrods.
These beautifully machined roller rockers are designed just for the direct injected Yanmar engines commonly found in the Pro-Stock diesel class of NQS pulling. These come optimized for the valve hight that the legendary engine builder Carlton Cope used in his Yanmar builds. Some engine building knowledge will be required when using these to set proper rocker arm geometry. We will gladly do it for you if you send us your assembled head. This kit comes with everything needed to install. You will use your factory rocker shaft and spacer springs. This kit replaces the old Harland-Sharp kit that was insanely expensive and had very inconsistent ratios. These are built to take 5/16” ball end pushrods.
