cobraws6

My SES light just came on and when I ran the code it was the P0420. From what
I hear this is always b/c of the cat. GM won't cover it since the warranty is only for '00-'02 FBody's.
I have been looking into doing headers but I am worried about passing emissions. I found some Mac mid lengths with a catted Y but heard those weren't very good. I've heard you can pass as long as you get the codes deleted.
Any ideas?

RPM WS6

iTrader: (3)

You've heard correctly. No sniffer test in IL. Get the proper tuning (or O2 sims), and no cats = no problem in IL.

Intragration

iTrader: (1)

I've got Kooks with no cats and there are no problems with emissions. You'd never know, and neither would the state...except for the delicious smell...

cobraws6

Is it hard to get the codes cleared? I've heard that the O2 simms are hard to come by. I have a mechanic I go to that may be able to help me out.
Know of any decent speed shops in Lake County? Speed Inc is a little far from where I'm at.

RPM WS6

iTrader: (3)

You don't want to "clear" the codes, you'd want to get them turned off.

Any shop with tuning software (LS1 Edit, HP Tuners) can kill the rear O2s. FLP or Speed Inc would be my recommendations for that.

O2 sims are easy to find on-line. Many site sponsors here sell them.

Intragration

iTrader: (1)

I've heard that the O2 sims don't work quite as well or as reliably as the tuning... Ryan, have you heard this? I just remember when I was doing research to get work done, I was sold on the program versus the sims. The fact that I had other things to get programmed out made the decision easier. As for distance, it's a one-time thing, and it could potentially be done very quickly. You could get it dyno tuned on the same day and get a few bonus HP.

SilverGhost

iTrader: (53)

back in the day when the only thing around was hypertech i ran 02 sims. never had a problem like that for several years.

i would just spend the $150 or whatever it is for speed to do a base pcm tune without having to put it on the dyno, take care of the 02 issues and some other nice little tweeks.

and yes i wouldn't put a mid length header on the car, you are right in what you heard. plenty of very affordable longtube designs on the market now.

RPM WS6

iTrader: (3)

I had O2 sims on my WS6 for 4 years. Never had an issue. I left 'em on and never bothered to turn the codes off even after I bought tuning software, just because I had them.