Removing Catalytic Converter?

[CrookedHalos]

I'm going to have to replace my exhaust pipes soon since it looks like its about to rot off. Thing is I don't really care to pay the expensive price of a new cat. I also don't want to have engine problems either though. Is anyone here running straight pipe? If back pressure is needed would a muffler be enough? Personal experiences greatly appreciated!

[jake88maro]

hay man ive had two festys where ive cut the cats off of. granted they both had full exhaust to a stock like muffler. it sounded much more breatheable if that makes any sense lol. and it gave me about 1 mpg and more top end id say. not much but noticeable!

[jake88maro]

both were efi also!!

[CrookedHalos]

I might just go ahead and do it. Ha Texas I can pass inspection without the car even being there with the OBD1. That ain't an issue here haha. I just didn't know if it ruined drivability somehow. I have a catless 04 mustang GT so the smell won't bug me either.

[crazyrog17]

I've never driven my Festiva with a catalytic converter, but I would wager a bet that it's just fine.

[bravekozak]

The main reason the cat is there, is for the robber barons who control the worlds South African platinum supply to get richer.

[B3Festiva]

Re: Removing Catalytic Converter?

I have a straight pipe all the way to an 05 malibu muffler. It uses stock hangers, pretty quiet, but sounds good too

170k+ B3 Festiva L slo-kart.

[hotfordcat]

I have a B6 swapped 91 no cat back to a V-Force muffler. Pretty snorty, and gets 38mpg.

[CrookedHalos]

What's a nice deep muffler for a B3? Something throaty. I hear Thrush Turbo 2 or something like that?

[Safety Guy]

My setups are as follows, all with stock exhaust manifolds, downpipes and Magnaflow low-restriction cats:

Luxstiva, B6 ATX: 2" piping with Magnaflow muffler

AquaMutt, B6 MTX: 2" piping with Thrush glasspack as a midpipe resonator and a cheap turbo muffler

Twinstiva, B3 MTX: 2" piping with Thrush glasspack and Magnaflow muffler

Prettystiva, B3 MTX: stock, unmodded

The midpipe glasspack really cuts down on NVH in the cabin. The 2" inlet/outlet Magnaflow cat will work on larger engines, so I doubt it's that restrictive for my little four bangers. The 2" pipe is probably overkill for a B3 and maybe even my stock B6s, but it works.

Karl

[DriverOne]

Re: Removing Catalytic Converter?

Luxstiva, B6 ATX: 2" piping with Magnaflow muffler

AquaMutt, B6 MTX: 2" piping with Thrush glasspack as a midpipe resonator and a cheap turbo muffler

Twinstiva, B3 MTX: 2" piping with Thrush glasspack and Magnaflow muffler

Which of those sound(s) the best? I have been looking at going 2" with a 22" glass pack and Thrush turbo muffler on my wife's B6. Are they "quiet (<92dB)?" Thanks.

[XFSE71]

I might just go ahead and do it. Ha Texas I can pass inspection without the car even being there with the OBD1. That ain't an issue here haha. I just didn't know if it ruined drivability somehow. I have a catless 04 mustang GT so the smell won't bug me either.

Doesn't the MIL illuminate and set a code for no cat on your '04? Cats are only there to burn the unburned/partially burned exhaust gasses. Performance should not be affected either with or without a good cat. The only thing you'll notice is the brown stuff in the air around your house. Either way the Festy doesn't care. Do you get smog where you are? Phoenix does and we all know about LA.

[Team Lightning]

I have a glasspack muffler in place of the cat. Then I have the same brand glasspack in place of the rear muffler.
I've had several comments on how good it sounds. Although now that they are getting burned out, it's getting louder.
Not unbearable but louder. It still sounds good to me.

[rmoltis]

I just ordered a new magnaflow high flow 1.75" in/out to put on. The downpipe coming off the stock manifold is 1 5/8. The cat itself is good for up to a 5.9liter engine so I would assume it doesn't hamper the flow too much for a 1.3 liter. Plus if you search the Web long enough you'll find a good deal. I got it for $68 now I just need to find myself a new exhaust bracket for my downpipe and ill be ready for everything.

[bravekozak]

Sometimes they check to see if its still there on a Drive Clean inspection. Most performance enthusiasts just have it bored out inside. Catalytic converter present. Check!