508 or 509 Purple Shaft cam

This post is a bit old, but I ran the solid 509/280 oval track cam in my 68 340 GTS, stock replacement pistons, 273 rockers, with X heads bone stock, headers, air gap, 750 holley DP, 3800 stall 727, 410 rea. ran best of 12.80 @ 105 in 1/4. Had it installed at 102. Nice radical idle and would idle down to 750rpm.