I'm sure the heads are the same , just NEW guides. The 110" heads are CAST and AFTER the valve seats are pressed in ,they BORE the seat and let the bore cut run down into the port around 3/8 " so there is no 'lip' from port to seat. The heads are NOT CNC ported ! The heads in my opion are good ,as the ports are good {shape} but ,too big ! They use a 93% valve to seat ratio !!!!!! WOW ! Stock H-D is 89 - 90 % and 'most' head porters use 89-91 % . When you use 93% ,you have NO seat to cut your angles on. Stock 110" has a very little 45 degree { .030 - .050 wide } and hardly no 60 degree { .010 - .020 wide } and if you install a 'smaller' seat ,you will have a lip ,because the port is already big. Only way to do it right ,is to weld the port and make it smaller. BUT , these heads do make pretty good power. I just 'shorten' the valve stem .010 then you can cut the 45 degree wider and get a 70 and 60 degree 'lead in cut' . I pulled 100 hp. and 114 tq. with stock heads and a Andrews 32 cams, stock T-B {46mm} dyno 250 I , 5th gear run SAE. Pulled 100 tq. at 2200 rpm. Only use a TFI for tune ,stock rev limit {5500 rpm} bike runs great. I can fax you the dyno. DEWEY