help me out
 

I have a carbed 6.0 lq9/ls3 right now that makes around 460 to the wheels thru a stalled th400 but I want more. Im itching to build a kb blown ls based engine and am wonderin if I should build off the 6.0 im driving now or the 5.3 I have in the garage. The truck is getting parked this week due to winter so tats not a big deak to pull the 6.0 to build it. Any pros to the 6.0 vs a 5.3?

Nobody? How do the ls3 heads respond to boost and boosted applications in the 700 whp range? If I go with the 6.0 I think id rather go with a 408 ci setup since it will be getting forged internals anyways. What do you think... 408, ls3 heads, kb 2.8l or so, and a boost cam? Will that get me to my power goal?

My opinion from reading, ls3 heads respond well as long as its got the correct cam for rectangle port heads and their flow characteristics. Your using atificial displacement so i dont think cubic inc matters a whole lot here. The 4.8 and 5.3 has proven you dont need big inchea to make big power.

Most use the 5.3's just because they are cheaper. If you have the 6.0 already I would use it over the 5.3

^^^ i agree use it. Its not like you need somwthing to fit the efficeny of a turbo. Benefit of a blower i guess

Would a 2.8l kb on a forged 408 with unported ls3 heads and a custom cam make 700 ish whp or do I need a bigger blower and ported heads? 700 is just a # in my head I make good power now but the truck doesn't scare me when I start It up so thats kinda my goal...

Im not familiar w blowers and dont know a thing about their size, but i would imagine unported ls3 heads flow more than enough for those numbers. With a D1 procharger I have seen LS1 make those numbers w 317s.