high flow cat???

[Guest]

I tried the search, which isn't really working. Neways, i was wondering if anyone has a good link or can point out a good catalytic converter for me. I have a 1993 CS with the 3.1. I've heard good things about Catco?? ne others. Thanx

 

- Drew

[dbtk2]

Since you are in MI and have no emissions testing if I were you I would just cut the cat off and put in straight pipe, but thats just my opinion. Its a lot cheaper than a high flow cat, and you know its gonna flow well.

 

Just my $.02

 

Shawn

[Guest]

I would try that, except that I heard the exhaust from the 3.1 smells like a$$ with no cat....

[Phat Pat]

any exhaust typically smells bad when the cat gets too old (rotton egg smell) but I think it would be fine if removed completely. plenty of people have cut off their cats, but someone who has can tell you for sure if it will smell or not.

[patgizz]

did not have any weird smell on the 91 when i cut the bad cat out and put in straight pipe. it was noticably louder even with a stock muffler.

[TeeJay3800]

I live in Michigan as well and have no cat (2.5" straight pipe in place of it). One advantage of living here is no emissions testing, so you can get away with it. I found the exhuast smell is stronger, but smells no worse than with the cat installed. There is no reason the 3.1 would smell any worse with no cat than any other motor. Be prepared for your exhuast volume to increase significantly.

[Z34door]

glasspack in place of the muffler so the ehxaust isn't too obnoxious

[Justin]

2.5" straight pipe in place of it

 

Are you running 2.5" pipe?

 

 

The factory piping is 2.25", just go to an exhaust shop, get a 3' chunk of 2.25 flared out on the end so it fits over a 2.25, then cut the cat out and clamp the pipe in. I've used my pipe section twice now, practically falls into place.

[TeeJay3800]

Are you running 2.5" pipe?

 

No, the rest of the system is stock. The 2.5" pipe lined right up and welded perfectly for me.

[dbtk2]

The exhaust definately doesn't smell any different, but as they said the exhaust is noticably louder. We removed the cat on both of our TGP's and went down to autozone and bought the 2 of the 18" long 2.25" pipe, one with both ends flared and one with one end flared, and then 3 clamps (one for each end and one to clamp them together), and then cut the cat off and clamped it in place and it is great. I think it cost something like $11.25 total to do that for each of the cars. IMO that is the best way to go and is much cheaper than a high flow cat.

 

Shawn

[RedZMonte]

i would suggest a carsound high flow cat. check e-bay they are cheap and very good.

 

 

shane

[SmoothSteve3]

ok guys, this is driving me nuts........

 

After many many posts about this whole cutting the cat off thing, I finally decided to leave it on because my 3.1 would loose so much low end torque (which is pretty much what the 3.1 is known for)

 

But now you guys are all saying that its a wonderful thing.....

 

I want a threatening sound from the exhaust, not a tin-can when driving.....so do i cut the cat out and leave the performance muffer on? Or just get a high-flow cat?

 

This is important for me, cause my stock cat is officially DEAD. The exhaust stinks like no other. So its basically decision time on my part.

[TeeJay3800]

If I lost any low end torque when I took my cat off, it was very little. With a performance/louder muffler, it is possible to get a rasp from the exhuast when you remove the cat. Using a resonator or a glasspack along with the muffler will get rid of it.

 

Like I said, don't worry about loosing much low end. There really is no loss and you'll make up for it in increased flow.

[Robby1870]

Yup, no wierd smells here and Ive had mine off for two years.

[dbtk2]

I don't know about the N/A 3.1's, but when I cut we cat off of both of the TGP's they both gained A LOT of low end torque. I think this is because it allowed the turbo to spool faster, or maybe the engine could just breathe like it was supposed to. And might I add one of the TGP's had a two week old high flow cat on it. With a cat on them (they were both stock when we took the cats off of them) if you stopped completely and put your foot to the floor the car would take off and chirp the tires maybe once or twice. With the cat removed if you stopped completely and put your foot to the floor the tires would spin up until about 20mph. And I am not exagerating at all, talk about a huge difference. Our 2 door TGP went from a 15.042 @ 91.90 to a 14.819 @ 92.72 and all we did was cut the brand new high flow cat off.

 

But I am thinking if you loose and low end torque, it won't be a noticable amount, but you will probably either not loose any or gain a ft.lb. or two.

 

Shawn

[Guest]

Alright i guess i'll just try this with no cat for a while, and if i dont like the sound / smell, i can always put one in. Thanx a lot.

 

- Drew

[Guest TurboSedan]

i had a local exhaust shop cut the cat out and weld in a straight pipe. it cost me like $60 altogether but i wanted it welded in and not just clamped. i definately gained some power, not much but it was noticeable. however, the cat had over 200,000 miles on it and it was starting to stink when i'd get off the highway so it was obviously plugged up.

 

the exhaust is more raspy now, and that is with the stock muffler. my TGP engine should be in my CS within a few months, so it won't be raspy for long.

 

joshua (just put my TGP motor on the engine stand a few minutes ago )