I was changing my oil today, and took the intake tube loose from the turbo to gain some room. I figured while I have it off, I ought to crank it up like this and see what my turbo sounds like. Well I did, and it wasn't any louder than with my stock air box hooked up. I revved it to probably 2000 rpm's, and it never made a peep over the sound of the engine. It would make a little sound when letting off, but nothing noticeable. Is this normal? My truck is all stock other than the 4" straight pipe. You can hear the turbo a little bit through the exhaust, but not the intake side. I know my truck isn't impressive at all with power, and I'm wondering if this has something to do with it. The 318 that was in it before I converted it to diesel pulled better than the truck does now in stock form. And it doesn't smoke at all loaded or unloaded, so I guess the turbo must be doing something. Thanks for any help, Alex