Is the advertised CC volume (59cc or 64cc) in LS6 heads before or after porting usually? In other words does it start with a 59cc CC, them have some volume added during porting? Or is the CC volume after porting? I'm not looking for 11:1, just don't want to pick a volume for 10:5 or so, and then loose some planned compression because the CC was enlarged during porting.

 

real 243 castings are ~64 CC. i think you might be refering to the PP ls6 style heads, which are 317 6.0 castings that have the chamber welded up to a desired volume.

 

yeah, I was talking about the PP LS6 heads. Thanks...

 

the process starts with the chambers being welded up and then CNC'd out to the requested spec, so if you order a 64cc head that is what you will end up with.