Removing Cat on 2013 R-Spec 5.0

[kav1ani]

Hello I have researched and it appears MSA is no longer selling test pipes... I want some more breathability for the engine but some more growl but not loud or drone really...

can I just leave my exhaust on and remove or hollow out the 2nd cats

and if an exhaust shop says makes a test pipe for me what will happen with the O2 sensor will it throw a code or do they have to wire it in the test pipe they make?

Input please and advice.

Best regards,
Jason

 

[TheDr9669]

There are no O2 sensors downstream from the secondary cat's, therefore no engine codes will be thrown and the car will still pass inspection. (At least here in Texas.) Just removing the cat's will not effect the sound very much so no worries on the droning aspect. I have had my cat deletes for >40k miles without a single issue. IMHO you should be able to notice a small difference in overall engine response and upper RPM performance. Nothing to brag about, but still there. (And every little bit always helps, right?)

 

[Paul]

There are a couple of ways that you can go about this; You can hollow out the secondary cats, (not really the preferred method since it add weird acoustics to the exhaust) you can have a set of test pipes made to replace the secondary cats, or you can buy a set of test pipes. The 5.0 and 3.8 coupe test pipes are the exact same animal, so don't let the fact that you can't find anything from MSA daunt you. Any of the vendors that sell 3.8 or even 2.0t test pipes will fit our cars. Just keep in mind that you need 2.

Removing/replacing the secondary cats on the 5.0 motor WILL NOT have any negative effects as the downstream O2 sensors are mounted after the primary cats, which are directly behind the exhaust manifolds. The secondary cats aren't monitored..