the more cool air you get in, the more fuel you can add...what about an intercooled STS? with a little tune froma chip would about make that puppy FLY!
I had a 1999 silverado LT.....5.3 automatic 4x4. With a cam (had to custom tune the ECM to match the cam cause it ran like crap), hypertech programmer, 459 pound per hour injetors, hotter fuel pump, adjustable regulator (for turbo use onle, I never turboed my engine, it was always naturally aspirated), throttle body spacer, aftermarket throttle body, dual cone ram/cold air intake, true dual exhaust with the cats deleted (there's a "fake" sensor that sticks to the bottom of the truck and plugs into the O2 sensors to give a reading that is correct, not sure how they work though) and a couple other odds and ends like a shift kit and HID's and this is what I came up with.
Truck 1
Truck 2
With my foot on the carpet it got about 9 MPG, but if I took my time, this thing got around 19 MPG. It would SMOKE most of the ricers out there, and EAT a similar factory truck as a joke! I only towed once or trice with it, but it dragged that trailer full of wood (2 cord) like a factory truck would go with no trailer behind it. LOTS of power to spare.
I wish I had the money or brass ones to throw a Procharger or STS at that thing, but I would have killed myself. I was only 19 or 20 when I had that thing, still full of **** and vinegar. I've calmed down with my driving, but I'm still a scrapper lol