not to thread jack but I was curious, what is the purpose of the ls9 gaskets?

ls9s are multi layered for forced induction

This is wrong, compression has nothing to do with the flow rate of the heads. I would look for some worked 5.3 heads if your going to pull your stockers for studs. I would also install LS7 lifters while your in there. I dont know what kind of power your looking for but on a dd I would just leave the stock heads on there and keep the boost around 10psi or less. The smartest thing you can do to keep that engine alive is to shift below 6k.

i am planning a 5.3 turbo build i was planning on spinning 6600, 6700 with boost 10-12 psi, right now im spining 6900 with no arps i was planning on putting in arps, no one has ever told me they were bad, so are they a good thing to do or not

just to clearify most the stock 5.3 gaskets are also multi layered steel (MLS). the ls9 ones just have more layers.

the 243 heads will not raise compression over the older 5.3 heads it will lower it but only to like 9:1. the whole more boost less compression thing is crap anyway if you ask me. if your going crazy with it sure but 10-15psi or so i wouldn't worry about it. when i do build my motor i'm going 9.8-10.2:1 depending on pistons and what not. but every body has there own opinion on that.

...and my opinion is in his other thread, which is about the same thing. :sigh: