[srossi5]

They are about 6-8 inches behind the primary cats

[Zap city]

Hows the burble and tone on decel. Looking for more of that here without the full expense of catbacks. Any issues with warranty in the future? Thanks for posting.

[srossi5]

Downshifts are louder especially when the rev match is on the car just sounds all around better with the secondary cats removed. Also when is tour or stealth you cannot even tell that the cats were removed.

[srossi5]

Not sure about the warrenty vut im not worried about it worst they could do is deny a claim if somthing on the exhaust breaks

[Richard0nee]

Sounds good! If there is an emission problem you can always put the secondary cats back on it would think.

[srossi5]

Originally Posted by CreativeDawn

I agree. I've noticed only a pinch more on Cold Start before I go to work in Stealth Mode that there is a little more rattle-noise due to the Valves being closed, but other then that when in Stealth at normal driving it seems the same.

Now when you have it in Track Mode, I notice a 25% increase in sound and a very slight increase (not much) in crackles and pops. So really its your choice in the end! Was it worth the 150/200 bucks I paid? Sort of...Would I do it again? No.

I think the car sounded excellent before and sounds excellent now. I think GM did an amazing job with the comfort area when inside the cabin. It sounds like we have no sound to our cars, but from outside it's a beast!

Some guy did Straight Pipes and I came across this video.

I agree with you when in stealth and even in tour you can barley tell the car is on just as it was stock but in track mode the car got a lot louder in my opinon especially when you stand behinde it. If you are just in the cabin it doesnt give you the full effect because of gm good job making the cabin quiet.

[ScottySheppard]

I own a 2LT with NPP. Removed the fuze (51) as soon as I got it home from the dealer. A couple of weeks ago I found a upscale speed shop in Reno that removed the rear cats (or "resonators" as they called them). They specialize in supercharger and turbo installs and their wielding is second to none. Took 1 1/2 hours and cost me $160. Well worth it. The sound is out of this world. Even the wife likes it. (She put a couple of Flowmaster 40's and removed the resonators on her new Chrysler 300C so you know she likes her sound). No codes after about 1000 miles. Highly recommend the mod.

[srossi5]

Ive had my secondary cats gone for about a month now (1000) miles and i still have not thrown a code i would check your welds on the pipes because thats what seems to be the problem with others who have thrown a code best of luck

[srossi5]

Originally Posted by CreativeDawn

So after the secondary cat-delete, I've noticed that my vehicle is now throwing CEL codes WITH the Vitesse Throttle Controller installed! I decided to remove the VTC and throw it in my glove box for safe keeping.

My vehicle kept having reduced power problems which I believe could be because of the secondary cat-delete pushing out more exhaust throw the pipes! Some may argue with me that this isn't possible, but I think anything is possible! So far the car sounds bitchen and the exhaust pops are like 30% louder now that the ECU/MAF have understood the new setup. I have to take a video to show ya'll.

Not to get off topic but how do you like the throttle controller is there a big difference in throttle response thanks

[Ace01]

You would think someone would have made custom pipes you could purchase so it bolts right in so you can reinstall the cats if you have to. Fab shops are you listening?

[Glen e]

Originally Posted by Ace01

You would think someone would have made custom pipes you could purchase so it bolts right in so you can reinstall the cats if you have to. Fab shops are you listening?

Not really, the secondary cats are welded in, so they have to be cut out which leaves bare pipe that needs to be re-welded ...it's a simple $100 operation to take them out, another $100 to put them back. Flanges woulsd be more expensive, IMO.

[SS 1LE]

Originally Posted by Glen e

Not really, the secondary cats are welded in, so they have to be cut out which leaves bare pipe that needs to be re-welded ...it's a simple $100 operation to take them out, another $100 to put them back. Flanges woulsd be more expensive, IMO.

...and possibly not have a good enough seal. The cat delete seems to need GOOD welding or some get a CEL.

[zSHOWTIMEz]

So do I wait until after the "1,500mi break in"
Or can I do this now with my 200 miles lol

Also do you lose power ?

[SS 1LE]

Originally Posted by zSHOWTIMEz

So do I wait until after the "1,500mi break in"
Or can I do this now with my 200 miles lol

Also do you lose power ?

Someone in here did a before and after dyno, and I am pretty sure he did gain about 3 hp or so on average by removing those two secondary cats...I think it is more so to be done for a little more volume though.