[JPK]

I've heard that our stock CAT is pretty high flow BUT...........

I'm considering a universal style high flow cat (probably Magnaflow) for mine in the near future. Hell, it's gotta be, at least, a little bit better than the stock one.

Will changing out the CAT cause a check engine light or anything like that? I heard of a guy on one of these forums and his guts blew out the stock CAT and caused his CEL to illuminate.

Input? Thoughts?

 

[LoungeLizard]

The guy with the stock cat blowing out would be me. I would stick with the stock cat because it was made for out cars. Usually when someone guts a cat they gain a little power, because its like adding a strait pipe, well, I think I actually lost a little power. An aftermarket cat shouldnt set a CEL, but it could.

 

[JPK]

The guy with the stock cat blowing out would be me. I would stick with the stock cat because it was made for out cars. Usually when someone guts a cat they gain a little power, because its like adding a strait pipe, well, I think I actually lost a little power. An aftermarket cat shouldnt set a CEL, but it could.

I hear ya but that huge, restrictive hunk of metal they called a muffler was also made for our cars LOL!

So you felt that you actually lost some power when your cat gutted itself?

I was also thinking of taking it back to the shop and letting them cut the resonator off and replacing in with straight pipe. I was told it's not causing any restriction but I crawled under there and looked at it and the 2.5" pipe looks to to step down in size right at the entrance and exit of it. I was worried about noise in the cockpit so I left it on. With the upgraded audio system, I think I could cancel that out when I want to.

 

[goofyguy]

you will need a o2 simulator. Also the cat is attached to a crazy pipe it wont be easy to change out becuase there is no shop that will touch a cat. You will need to be very careful on who you see the create it as well.

 

[JPK]

you will need a o2 simulator. Also the cat is attached to a crazy pipe it wont be easy to change out becuase there is no shop that will touch a cat. You will need to be very careful on who you see the create it as well.

If that's the case, I think I'll just leave it be and just go with the resonator removal and cross my fingers for my SCdyne header to show up soon.

They cut out your resonator to do your dual mod, correct? If so, how loud is it inside your car now? Is it tolerable?

 

[dL_RL]

The guy with the stock cat blowing out would be me. I would stick with the stock cat because it was made for out cars. Usually when someone guts a cat they gain a little power, because its like adding a strait pipe, well, I think I actually lost a little power. An aftermarket cat shouldnt set a CEL, but it could.

Jesus, just because the CAT is made for our cars does not mean it should stay there. I agree with JPK. LOL! our mufflers are made for our cars, so we should just keep them on! our stock intake is made for our car, so why upgrade it? our ECU is made for our cars so why modify the signal!?! LOL!

 

[Redlinekid_04]

WORD!!!

 

[Tom01SC2]

The cat is one of the biggest units GM has in their bin. I believe it was originally meant for a truck, from what I have heard it is pretty high flowing. There are plenty of other things you could do before changing the cat...

Tom

 

[goofyguy]

its louder and yes the resonator is gone. Its tolerable I guess to an extent I have to take it on the highway to see what its going to sound like at 80 though.

 

[Vita]

high flow cats are really just cats made for bigger engines. also, did anyone notice where the o2 bung is, they stamped in the exhaust piping, i imagine that's pretty restrictive right there.

 

[goofyguy]

im gonna go elsewhere to get a test pipe made becuase of the wild design I have a guy that may or may not wanna deal with it. He might do it of me but it is not legal for him to do so. If he does perhaps the make of many or these may be possible.

 

[Redlinekid_04]

now thats a high flow cat.

 

[Catshreds]

I guess happiness ISN'T always a wet pussy!! LMFAO!!!!

 

[RedLined]

Our cat was originally used for gm turbo diesel trucks, so i'm guessing an aftrermarket one wouldn't be any better. As for the resonator bit, i cant stand how buzzy and high pitched an exhaust system sounds without one. But hey, whatever floats your boat. Though some parts on our cars are not worth upgrading, some are definately a must. Like our pos tach, exhaust, intake, and air/fuel programming.

 

[BlackRedline04]

I'm sure california has restrictions on this

 

[Redlinekid_04]

Yes animal cruelty is big in cali......

 

[Vita]

Our cat was originally used for gm turbo diesel trucks, so i'm guessing an aftrermarket one wouldn't be any better. As for the resonator bit, i cant stand how buzzy and high pitched an exhaust system sounds without one. But hey, whatever floats your boat. Though some parts on our cars are not worth upgrading, some are definately a must. Like our pos tach, exhaust, intake, and air/fuel programming.

have you seen the a/f ratio? if so please show us all...

 

[BlackRedline04]

Yes animal cruelty is big in cali......

haha, i meant smog, but yes animal crulety as well

 

[RedLined]

have you seen the a/f ratio? if so please show us all...

No, but i do have an a/f ratio gauge and it did show that the RL was running only slightly leaner than my old sc2 which only had intake and a tb. Im guessing its somwhere around 13.?:1 at 6500 rpm. I could be wrong, but wouldn't adjusting the ratio to run leaner, but not engine destroying lean, result in more power?