i have a well tuned 1500hd 2006, pretty much every bolt on except long tubes and a stall convertor. i found a set of heads off of an LQ9, re-worked, for about 800 bucks. i was told these will bolt right up on an LQ4...? i know ill need to re-tune. now i know the lq9 has flat top pistons, lq4 has domed. what is my compression ratio gonna end up as? will i lose compression? do i need to shave the head? cuz the cumbustion chamber is bigger on the lq9 heads...anybody do anything like this before? ive heard it will reaaaaally wake up that and im doin a cam and valve train from thunder racing...little bit lumpier. im loookin to reach the 450+ mark..will these be good enough?

If you want to hit 450hp mark get the lq9 heads. The heads aren't mandatory but will make it easier to meet your goals. When you order your cam from thunder racing tell them what you have and what your goal is and they will point you in the right direction cam wise without up selling you on stuff you don't need. Since the new truck engines are of the LS1 series you might want to create an account with LS1.com. They have alot of guys making big power. LS1 to LQ4/LQ9 swaps in camaros and vettes are very common so there are guys very familiar with the combo of parts you want to put together.