I just contacted Comp Cams and they are using these springs on their Xtreme Energy™, XR264HR Cam ...This cam is identical to the Howards HRS-CL110235-12
Here are the cam spec's for both cams:
http://www.summitracing.com/parts/HRS-CL110235-12/
http://www.compcams.com/Company/CC/c...?csid=157&sb=2
If you look at the bottom of this page, it gives u the additional parts that are needed and you will see they are using the CC-981 springs...
http://www.compperformancegroupstore...ry_Code=RFHRXE