silver03gt

I also have an 03 auto, SLp LM1's, Mac O/R pro chamber, 75mm t/b, ported plenum, CAI, K&N, U/L control arms, 275/40/17's in the back, Diablosport predator tuner, ect... I would have to say the best money I spent was on the tuner, even if your buddy is gonna tune the car, it's so worth having and doing it with that, You can alter so many things from shift points and firmness to spark advance and O2 sensors, I don't have MIL's the tuner took care of it for me, Where you have an auto like I do, I reccomend you get a tuner, it's worth it more to us that the 5 speed guys. A lot of people like the SCT, but I love my Diablosport, basically it's best to get the one that your local dyno shop is more familiar with,,,, Just my.02,,,,,,,,,, If your dead set against a tuner, then do the control arms and a t/b..... much better throttle response in the midrange and great traction.