Can you do this without any problems? (I dont have any emmisions), will I throw any codes?

 

[QUOTE=LS1C5Vette;1558351466]Can you do this without any problems? (I dont have any emmisions), will I throw any codes?[/QUOTE

Yes, you can remove them and you'll have a new definition for LOUD.

High Flow custom cats only cost you a few horsepower at the most at the rear wheels if you're doing this for power increase and later have to sell or have to pass emissions.

I removed my stock cats when I installed headers and lost one set of O2 sensors, I Lingerfelt makes a wiring harness so you can run the rear O2 (I think they switch faster) sensors in the front holes.
I had to delete the rear sensors with my EFI Flashscan.

If you just remove the stock cats, you may not to have to do anything. Most muffler shops won't do this, you may be on your own. I welded up my own tapered (from the header flange) connectors.


This is all a little foggy now as it's been several, like 5, years.

Cheers, Curt

 

So if I do this I wont get a CEL?? I am doing this for sound, will it be louder with my stock exhaust? Thanks

 

You will get a CEL. You can tune it off or use O2 simulators. It will be loud, some say smelly (I didn't notice any difference without), and you will gain some HP/torque.

 

Thats what I want LOUD, I am going to order some o2 simulators today, will these work http://cgi.ebay.com/ebaymotors/Musta...ayphotohosting, I dont see how w/o any wires...

 

I'm by no means an expert but over in C5 General there's a thread on cats - check it out:

http://forums.corvetteforum.com/show....php?t=1588250

 

Sry to bring this back from the dead but does anyone have a sound clip of a c5 with Lt's, no cats and straight pipes?? (this is the setup I will most likely have) has anyone actually noticed a gain in removing the cats??

 

Here is mine with the LTs with an Xpipe and no cats and straight pipes. I do have the dynomax bullets in the place of the cats. I have another video of it without the bullets. It was way too loud.http://www.youtube.com/watch?v=ZdSyrp_1mK0

 

here it is with no cats or bullets. Notice how raspy it is http://www.youtube.com/watch?v=xEI04...e=user&search=

 

I think those would be a waste of money. I may be wrong but they look like a joke

 

OK, so for all you naysayers.......

i got a used midpipe exhaust system (from stock exhaust manifolds to thhe muffler flanges.... had the muffler shop remove the existing midpipe and cut the cats out of the used midpipe (fouled cats) and put an X in place of the cats...... left the "H" in the pipe and hooked it directly into the factory exhaust manifolds....

put in 160 degree therm and with all the garbage on this forum about reducing temp.... I have been doing the same on all 3 of my vettes and not one hose failure, no AC problems, never overheated in traffic, always stable and dependable. I see 180 degrees in the summer and 165 in the winter , cool but water gets hot enough for the heat in Florida.... also GM tests show the crossing between longevity and economy cross around 175 so..... how do you argue with that... ?

1) It is not as loud as headers on the stock mufflers with an X
Cruise at 77mph has the same cabin noise
When you get in it it sounds throaty but not "ticky" like headers.
Has to be making additional HP but hard to say.
It is NOT loud ! Louder yes but not tremendously louder even when hammering on it.

2) It smelled before I adjusted the program for the removed cats, now I smell some fuel when I get on it hard and come to a quick stop, otherwise no issue.

3) The gas mileage went from 30.1mpg hwy at 77mph cruise on 100mile trip to 32.0mpg at 77mph on the same trip

4) Temps are cooler in the cabin i believe due to no cats and thermostat.

5) it did set a check engine light and will need O2 simms or programming to put out the light. The rear O2 sensor measures the O2 left in the exhaust after the cat..... it will obviously have more O2 since the slighly left over fuel is not burnt in the heat of the cat.....

overall I am happy with this configuration and have done it on every one that I have owned,,,,,, never any problem and all have been over 100k miles when sold.



Rick