Z51vette88

Hey.

Im looking to give my c6 base a little more rumble. I have stock exhaust with the npp on my 2008 z51

Has anyone ever gutted there cats or put a flange on each side of them to swap them in for emissions?

Any videos would be great too.

Thanks Jared

el es tu

Heres an example of someone with a stock GS (same exhaust as your 08) and gutted cats




I cant tell you to do it because some folks hate it while others love it.

Z51vette88

Yeah thats the one an only video I can find. I did message him to get some info but no response yet.

Lol I love the backfires on de-acceleration

el es tu

agreed!

ls1121

depending on where you live gutting cats could cost you a lot of $$$$$. Don't get caught.

Z51vette88

I live in windsor canada. Not to worried about the cops in the area. All my cars have been catless with cutouts an no problems. Also im only putting about 3000kms on it a year.

Will I throw a cel if I gutt them? Im more worried about that

el es tu

yes secondary o2 cel for cat ineffciency

the cels for this are easily turned of with a handheld tuner or laptop tuning setup

a trick some do is take two spark plug nonfoulers and stack them add them to the cat then put the O2 sensor in - this allows heat but limits the gasses getting to it so its less likely to throw a cel. before installing youll have to drill out the top nonfouler so the O2 sensor probe will fit in. Note: this doesnt work for all cars all the time - it can take some experimenting with different length nonfoulers (which are cheap anyway - the labor would be the bad part), but I believe a few folks here have tried it successfully.

examples from other types of cars (just google spark plug nonfouler O2 sensor)





EDIT: remember you'd do this on the secondary O2s which are useless other than monitoring catalytic converter performance - not the primaries (closer to the engine) which are used for your engine's performance

Staffah

You would throw a CEL because of the rear O2s. They monitor the efficiency of the cats. However, you can tune them out.

carpe dm

Don't waste your time and my health.

Z51vette88

Thanks guys an yes I am familiar with the 02 defouler an I will be tuned in a few months.

c5wolf

Without forced induction you might actually run a little slower.

mdchaser

There are dummy pipes you can buy that simply replace the cats... They aren't very expensive and they would allow you to put your cats back on if you ever needed to. I did them on my GS and it is much louder, a little to raspy for my tastes but I'm going forced induction next week so it should help there. I picked up a noticeably amount of power with the dummy pipes N/A, couldn't tell you how much but I was able to easily feel it (10-15hp maybe???).

Z51vette88

Where did you grab this dummy pipe? Or do you mean you cut the cat out an replace it with a pipe with 2 flanges? An how hard was it to do? Just grabbed the car an haven't really bèen under it..

An raspy, as in backfires on de-acceleration? Do you have a video laying around?

mdchaser

I bought these:


https://www.texas-speed.com/p-1181-m...g-05-ls23.aspx

I don't have any videos and I'm not sure how to describe the rasp... It just sounds a bit more raw than I would like, not bad necessarily and it is mostly in the cabin. From outside the car I think it sounds noticeably better. I have no idea how these sound compared to just mulching the catalytic compound, my guess is that would be a bit quieter. I even installed them myself, just had to buy some bolts and get it on a lift.

Z51vette88

That's what I actually wanted. I didn't think they made anything. Did you get a engine light?

Would you be able to get a video for me. If you dont mind

I also have the npp exhaust. Which worst comes to worst ill just plug the fuse back in. But I like loud. Im only 25 years old

angeno

Personally, I've always found that gutting cats gets you in hot water with the ASPCA. If they're driving you crazy and pooing in your garden, better to drown them or boot them across midfield like Uwe von Schamann in his prime. ;D

mdchaser

I can try for a video but I won't have the car back for about a week and a half (getting a centri blower installed)... I did eventually get a light but I had it tuned out, a good tune is pretty much mandatory on these cars IMHO, nets lots of power for little money. It is loud but not as loud as I want, if you are not sensitive to noise then these definitely won't bother you. I put on B&B fusions and leave the exhaust open unless I'm driving past an officer, then I shut them for a sec .

Z51vette88

Okay thanks. I thought at first it was to loud for you. I will be going to get a tune in a couple months when the dyno is available threw livernois motorsports. An rite now i believe my npp solinoide is shot. It wont close when I plug the fuse in...

timd38

Hope you good in stripe for braking federal law!

Z51vette88

Lol you have to take risks sometimes