[Glen e]

Cut out the second cats today and now the gm/borla perf exhaust has solid bark on cold startup. very satisfied with this change.
1. still no drone
2. nice growl when ever you are on the throttle
3. no CEL

Note: we have no emission checks in Fla, your state may have a prob with this mod.

thanks to Ricardo at phasetek and Tr6 for counseling with me on this. The current advice is dump the cats but not the square resonator in this system.





Cold start clip below

[MarkZ]

Nice! Looking forward to hearing what this sounds like.

[Glen e]

http://youtu.be/h5kOUoMNoiE

[Goobaba]

Nice sound, getting my Gm perf exhaust installed as I type this. I'll post some vids if anyone is interested.

Edit: In GA I don't think removing the cats is an option for me

[cellsafemode]

Technically in no state is it an option. Just a matter of if you'll ever be caught.

[Modshack]

Originally Posted by Goobaba

Nice sound, getting my Gm perf exhaust installed as I type this. I'll post some vids if anyone is interested.

Edit: In GA I don't think removing the cats is an option for me

The secondary cats are unmonitored. The primary ones are still in the system up close to the headers and do most all the work. No CEL's or emissions issues will be triggered.
On the LTi, they are the Squarrish cannisters just past the Primaries. Most companies working on exhaust systems for the SS will run from the primaries back as there is disconnect/clamp between the two.

Here's what the SS looks like underneath:

[Glen e]

Originally Posted by Modshack

The secondary cats are unmonitored. The primary ones are still in the system up close to the headers and do most all the work. No CEL's or emissions issues will be triggered.
On the LTi, they are the Squarrish cannisters just past the Primaries. Most companies working on exhaust systems for the SS will run from the primaries back as there is disconnect/clamp between the two..

Correct, and totally reversible for cheap if I sell the car or a dealer wants to be a jerk. Mine are in my workshop storage:

[bdar66]

would you say doing this has changed the sound of the car or just made it louder?

[Glen e]

Changed the car....youtube video above, you decide

[RSKUSTOMZ]

So why are they saying leave the resonators?

[Modshack]

Originally Posted by RSKUSTOMZ

So why are they saying leave the resonators?

There ae no resonators. Some have confused the secondary cats as resonators though. They're not.

[Glen e]

Originally Posted by Modshack

There ae no resonators. Some have confused the secondary cats as resonators though. They're not.

Correct.......

[PolynesianPowerhouse]

Originally Posted by RSKUSTOMZ

So why are they saying leave the resonators?

resonators are generally smaller mufflers. that's the purest definition of a resonator. these 2nd cats, do resemble short resonators/sub-muffler/small mufflers.

after being under the car today, theres the cats, 2nd cats...then the rectangular resonator/small muffler (which may or may not house an x pipe), right around the tie brace, and then the muffler at the tail end.

[Modshack]

Originally Posted by PolynesianPowerhouse

resonators are generally smaller mufflers. that's the purest definition of a resonator. these 2nd cats, do resemble short resonators/sub-muffler/small mufflers.

after being under the car today, theres the cats, 2nd cats...then the rectangular resonator/small muffler (which may or may not house an x pipe), right around the tie brace, and then the muffler at the tail end.

See my pic in post #6 If you're referring to the V8 LT1 set-up. Those square cannisters are the secondary cats. There is an X junction further down where the pipes come together in the central tunnel area. I wouldn't call it a resonator. Mishimoto has verified CATS with pics of the insides on the rectangular cans. The pics Glen has shown are for the V6. Different physical layout..