I got a 2003 SS Monte Carlo with the 3.8L. When i bought it from original owner it came with dual flow master 40`s.
What are some other engine mods i can do for more performance for decent price?
Maybe add a Supercharger, Intake, Performance Chip? Its my daily diver

 

well i see no downside of having a fast DD. so check out 3800 Performance - high performance aftermarket car parts for your Grand Prix, Monte Carlo, Impala, Regal, Bonneville, and V6 F-body!!
they have some nice stuff there. maybe even add a turbo. that will really add a little jump to your car. Overall your car looks good as it is, so i would stick with performance mods

 

Cold air intakes and headers are a nice start. I would suggest, if you want a decent amount of power, either pick up an l67 to swap in, or do a turbo kit. If I could do it all again I would go turbo, hands down.