Alright, so I've got a '95 Chevy Silvorado 1500 Z71 4x4.

My situation: the 5.7L is currently putting out ~ a mere 210 hp or so, and around 275 ft-lbs of torque at 4000rpm's.
I'm getting a little fed up with not being able to sufficiently pass the minivan in front of me that's not even doing the speed limit. I don't want to sacrifice gas mileage for power, and if possible, I'd like to increase both efficiency and gas mileage.

So my question is, what's the best way to go about that?

 

I had a 94 as well. I saw a back in the seat change when I added the following to allow the engine to breath. The 5.7 REALLY responds to intake, exhaust changes, more so than the 5.3.
1.) Helix Power Tower TB Spacer + Cone intake spacer below Filter = Ramjet Effect 8-12hp easy
2.) Headers - Any brand, I suggest Borla, B&B or Gibson 20-30hp+ easy
3.) MagnaFlow Dual Cat Back 15-25hp easy
4.) K&N 5-8hp
5.) Superchip or Jet Chip 10-20hp or ECM re-program - Ron Zimmerman, Hemet Ca - Or maybe the Goodguys Rep here can do a swap (best in gains)
-->>>Let the engine Breath and you will see great gains from that 5.7. It's there guy, you just have to let it breath.
As for Gas MPG, you will see a real DROP in RPM at speed and that = better MPG.
GL
Greek