What ls series parts are you able to bolt on an lq9? Like will an ls1 take fit on the top of an lq9 easily? I'm looking at making reliable power for a chevy 2500 hd without getting too crazy. I live in California but I can't go too crazy for smog reasons

 

Yes it would fit but the LS1 intake would be a serious downgrade on a LQ9.

 

The nnbs intake is your best bet for that but will cost you.
Othetwise a small torque cam like the tsp high lift stg2 truck cam would work great and still pass any sniffer.