Unfortunately there isn’t cat-back systems (that I’ve seen yet) available for our car. You may want to ask some of the Monaro guys what they’re running. Few the first few months to a year after this car hits the street it may be more of an “experimental” period where you may have to come up with your own setup with a local exhaust shop. I know I’ll probably be spending quite a bit of time with the guys at FLP custom fitting my own setup initially.
The problem with running without cats on an LS1 is that it has a real raspy/poppy sound to it. I don’t care for it. But that subjective to each person. There really is minimal gain to be had running catless vs. a high flow cat (such as a Random Tech unit) and in actuality you may lose some torque to gain 1-2 additional HP. Then there is emissions testing. With the new OBDII scan, with O2 simms you will pass, but if they do a visual, you can quickly get caught, they do have under car mirrors you know. Is that worth gaining a couple HP?
What I may do, is using FLP’s quick connect system is create flanges at each end of a high flow cat that will meet up with the rest of the exhaust plumbing. I will also fabricate straight out “off-road pipes” with flanges on each end that I can run all the time with O2 Simms. Then come emissions testing time, quick swap out the off-road pipe for the cats, pop them in, take the test, pass, come home and switch back to my off-road pipes. I wanted to do this on my Camaro, but my piping is 3.5” all the way and FLP’s max is 3” I think.
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