I have a 97 Sierra with a 5.7L, rcsb. What I have done to it is, true dual exhaust, k&n intake and 180 degree thermostat. When it gets a little nicer out, I'm planning on doing more upgrades to it. Here are a couple of my plans let me know what you think. Underdrive pulleys, Nelson tune, MSD plug wire with Boush +4 plugs, Headers, also maybe posi track with 373 gears. Tell me what you guys think? Also if you have anymore tips I would appricate it.

With all that, sounds like you need wheels and a lowering kit as well.

I have a 97 Sierra with a 5.7L, rcsb. What I have done to it is, true dual exhaust, k&n intake and 180 degree thermostat. When it gets a little nicer out, I'm planning on doing more upgrades to it. Here are a couple of my plans let me know what you think. Underdrive pulleys, Nelson tune, MSD plug wire with Boush +4 plugs, Headers, also maybe posi track with 373 gears. Tell me what you guys think? Also if you have anymore tips I would appricate it.
I'm not 100%, but i don't think nelson Performance can tune a non LS-based engine.