Lbs of boost with stock Roush pulley on 5.3?
 

I have read tons of threads and still can't tell what to expect from the stock pulley on the roush tvs on a bone stock 5.3. I have seen posts anywhere from 6lbs to 11lbs. I am installing one on my 12 Avalanche and was thinking about putting a 10% overdrive pulley on during the initial install so I can get it tuned once and be done with it. Which brings up the second question from what I have read the 10% overdrive will add 2 to 3lbs?

My educated guess is a Roush with a 6.0 would be 5 to 6lbs. A 5.3 somewhere near 7 to 8lbs and a 4.8 in the 9 to 10lb range. I guess this is why they had one pulley for all three setups.

What have you guys experienced?

My roush 1900 with the stock pulley made 6psi on a 5.3.

Did you have a cam or headers on your 5.3 at 6lbs?

My bone stock 5.3 with the 1900 made 9.5 psi 407rwhp/425rwtq mustang dyno. I now have cal speed LTs and y-pipe, no cats and make 8psi.

Just cat-back exhaust, LS9 cam.

9lbs is my target. Its crazy yours made 9.5 and smoke made 6lbs this is why I started the thread because I have seen so many different results. I would not have thought a ls9 cam would have made a 3lb+ difference.

Just depends on what mods are done to the engine and how well it breathes.

I would put the OD balancer on and get it tuned all at once , but you might run into valve float with stock valve springs .

completely stock mine makes 8#'s

You need to remember, that boost PSI is a measurement of restriction, not a measurement of power.

I realize boost is just a measure of resistance. The interesting thing to me is the 3 different results on bone stock trucks ranging from 6lbs (from a pm I received not the 5.3 with a ls9 cam) one with 8lbs and the last with 9.5. The only other variable I could think of is altitude or maybe different heads from the different year models? When you get into mods such as airbox, headers, cam, TB, then of course that changes everything.

This is my third supercharged LS vehicle so I have a little experience with mods and the effect of mods on a supercharged vehicle. I am trying to predict a base line of what to expect. If I put the tvs on and end up with 6lbs I probably wont be happy but on the flip side if I throw a 10% od balancer on and am at 12lbs or more I have probably pushed the envelope too far.

Thanks for all that have given your results and input.