The only concern I have with your plan and money spending is you are still rod limited to ~550rwhp on gen3 rods

I cannot comment on the cold start noise, as Ive pretty much felt any motor I built or had built made a little noise when cold. I just fear you're chasing a ghost here and still leaving the gen3 rods in and cutting yourself short on reliability

 

ill do rods and pistons


found a BTR stage 3V2 truck cam for cheap. for my power goals i wonder how it would do with boost?
218/224 .553”/.553” 110 BTR