which 509? the 108 or the new 114 LSA? Mine would not fit in my 68 383. I ended up with a MP484 which worked great for the 3 hours that it lasted. I would think you are better off with what you currently have. Save the cam for another build or un load it. You need a far bit of compression (10 or better) and good converter and gears to make it work, There are better grinds out there.