Need help (Car is Bogging)

[04RedLine04]

Was up team..I have a couple of question so here I go. For some reason I have been noticing my car bogs alot during low rpms and sometimes high rpms, I have raced numerous cobalt SS & Redlines and for some reason everytime I am rolling lets say 2nd gear maybe 3rd they pull away about a car and keep pulling.These cobalt and redline have been stock or with minor modifications.I have an 04 redline with mainly every recall in the system done to it but for some reason I am having code p0420 pop up I know that its probably due to the fact that I have headers and High Flow cat Now what exactly does this code do to ur car I heard from someone that it could do someting with ur car timing(not sure please help on this ) But overall i feel the car slower with headers and high flow cat im not to good with this but i heard hp tuners can delete that 02 sensor or the 02 simulator. please help me out on this cause I am not sure if my bogging issues are from that or from something else but there is something wrong Thanks For any help

[TheWastedYears]

That's the catalytic efficiency code. It means the downstream O2 is reading similar to the upstream O2. This could be a bad cat, or a bad downstream O2. Or a buggy tune.

As for why you're losing... 04s have a shitty tune. It makes the car lurch a lot. All over the place, but moreso in the lower revs.

Find someone w/ HP Tuners and pay them $100 to license your car and flash you w/ an 05. You won't regret it.

[Shabodah]

Or you can have a dealer do the stage flash, if you're interested in going that way.

[04RedLine04]

Yeah I would like to do stage kit but will it fix the problem ?? I feel that its going to mess up the car even worse with stage kit

[SilverRedLine04]

nah gms 04 tune nearly matches 04-05 tuning.

keith-