Aaron, any updates on this?
I personally would NEVER run an OEM cam as they are such a compromise over just about anything out there. With the technology that has come out in the 30 yrs since that LS5 was made is night and day. With a few "minor" tweaks, that LS5 even with 9-1 comp, can make the power of an LS6, proven many many times by a number of guys out there.
I will admit, the stock manifolds I have no idea what that will effect. IF it were me, I would swap out the heads for the mildly ported oval port closed chamber heads, get the matching manifold and have it ported, and get a cam from a cam guy. In Detoit, talk to Chris Uratcko or even Mark Jones on here. The cam,heads,intake to manifolds is the package that needs to all work together to be there best.
FYI, I have a mild 427 with the ported closed chamber oval heads, flat tappit, but 12-1 and a strip dom intake with heads. Been mid 10.'s back in the 90's with it and it's set-up for nitrous. Was very very street friendly.
Or check out Mark Jones's build here for an idea:
https://www.yenko.net/ubbthreads/ubbt...opics/646361/1
YES Mark did put on some things you don't want (intake, headers, el. water pump drive) but you can get the idea