I've got a 7875 on3 that will be going on my bone stock 5.3 in the following weeks, probably won't make it to a dyno until later summer tho

 

Turbo size is what's needed to determine that. The ar numbers will tell you how fast or slow they spool. We also need to.know what your plan is. Do you an on running it deep in the rpm range for track driving and max power? Or are you planning on street driving it which would require a faster spooling turbo and now midrange and rpm is where your living. You'll need to chose the proper cam turbo intake manifold etc. If Simply achieving your goal of 500hp I'd say you.could simy achieve that on around 10lbs of.boost on a stock5.3. The rule of thumb is at 14.7 psi your hp will.be 2x more than your stock na hp.

 

I hope he has his turbo picked out by now since that was a decade ago