[GordonC]

Ok! A little back yard engineering and we have a super duper high performance spring tester courtesy of some of the ideas you boys have shown here. Picked up an el cheapo $12 scale from Wally world. Grabbed an old scrap valve I had laying around. Cleaned it up and chucked it up in the drill. Threw the scale on the drill table. Leveled it. Placed a piece of scrap steel on it for protection. Set the needle to zero. Set the handle to stop at 1.675" and then tested all the springs. Here are a few pictures along with the results.

I wondered about the 2 grooves on the valve. Interestingly enough the valve spring locks have the width on the keeper to fit the second groove perfectly. The top groove is somewhat larger so they will probably fit on there as well.

Oh, just for grins because there was some concern for these being progressive wound springs installed incorrectly I tested them from both sides and the posted numbers were the same in either direction.