Headers for an LS V-8

Does anyone make headers for the V-8? Also has anyone dyno'd some of the existing mods or are the numbers out there just guesses?

no headers that I know of - I've even taken it to a couple of local shops - once they look under the hood.....

we have dynoed a few times:
- new intake tube and hi-flow filter - 13rwhp
- new exhast - 7rwhp
- ram air - 3rwhp
- NOS ....

some guys are trying out a new diff / rear-end right now.

Thanks Quik.