I have a 00' SS M6 with a lid, and loudmouth II catback and other mods in sig.

I'm installing Jet hot headers and a catted Y, Some new stock LS6 heads with 918's. And I just installed a 220/220 114lsa since it's all apart. I've tried searching...

How much HP should I expect to see at the wheels?

 

350-370 maybe

 

Oh, and a 180 SLP Thermostat...not that it matters much.

 

I have the same setup as you except my cam (218/224 535 114) is a little smaller & I have stage 2 ported LS6 heads...tuned with HPTuners...dynoed 400 HP at the wheels