Alright gentleman, 65mm holset, 100lb injectors on a stock 4.8. Running 8-10 lbs of boost. My question for you guys is at what point do I need to upgrade my fuel pump? It's a 2011 Sierra. I have a bosch 044 but have yet to use it. Just curious

 

Is your truck tuned and running with boost?

 

Yes sir. Tuned and moving along nicely

 

How is your fuel pressure under load?

 

That's what made me ask. Feels like it falls off a little when my boost gets up to 10lbs

 

A gauge to verify works better than guessing

 

I would upgrade pump with boost its not real expensive and not that hard to do... I have a walbro 255 lph in mine at 9 psi boost with 60lb injectors with no hiccups or problems what so ever

 

Whats your setup? Im looking at a used D1SC tuner kit for my non flex fuel 08 denali and I need some fuel system guidance.

 

Why 100 lb injectors for only 10 psi on a 4.8L?