I have a 1999 s-10, with a inline 4 engine. I want more low-end torque mainly what are some upgrades I can use? Don't say turbo or Nos.

well you can get an aftermarket exhaust, intake, or header, those will all give you more power. Maybe even an upgraded ignition system or a carb. :)

Which one of those will give me the most power? The carburator? Also, what about high compression pistons and performance computer chips?

I have a 1994 4 cyl. S10 with 22k original miles and it's economy only. I could beef up the 4, but I don't think it's worth it. What will it have 120 hp?
Ah-to dream----
I have seriously thought about putting the drive train and COMPUTER out of a crashed late model Z28 350 Camaro? It would take some measuring , some work and a v-8 installation mod kit. I'd have to cut a driveshaft and mouse a few things.
That would make a dynamite combo with a set of mellow pipes that would pass emissions and get decent mileage!
I had a chance at a rusty 1985 Z28 for $500,-it ran well, but too many toys right now. Another time maybe.
License plate Z28S10 ?
:D

I have a 1999 s-10, with a inline 4 engine. I want more low-end torque mainly what are some upgrades I can use? Don't say turbo or Nos.
change your exhaust: header can get from pace setter, high-flow cat. can get from truckperformance.com, ("might have to lie about the year of ur truck and or remove ur cat. urself because of emission laws"). flowmaster muffler. K&N air intake, run about $225, you'll feel the difference, sound way better also. also change fan to electrical, less drag.