Failed emissions in MO

[progress1vebmx]

First off, it didn't have the cats on...I better put those on...anyways...EGR is capped too..

HC - 6.8063 out of .8
CO - 103.68 out of 15
NOx - 1.6673 out of 2.0

How much improvement will my cats do putting them back on and is there anything else I can do to pass?

 

[gofstbuick]

Judging from those numbers, it looks like it's running really rich. IMHO a functioning cat and EGR is almost required for I/M 240 type dyno test. Once you do get it running leaner, the NOx will go through the roof. A three-way cat reduces NOx, HC and CO. The EGR system will control Nox. A properly functioning O2 sensor will keep the mixture close to stoichiometry.

 

[progress1vebmx]

Any suggested cat? Right now I am runnin 009's and a thrasher 93

 

[gofstbuick]

Any Three way high flow or normal cat should do the trick. Random tech makes on, so does catco. ATR and Aggressive performance sells them, and so does Ramchagers, Poston, Kirban, FullThrottle Speed & Style, Cottons performance etc.,,,
You choose any of the vendors and you will be taken care of. You probably could visit your local muffler shop for a Three way cat, but most of the vendors have cats with flanges, so you're not cutting up your y-pipe. You do need to specify a Three way catalyst.