ThickLizzyVetteswerv

I am now shopping for a replacement main cat for my '89. I'm not replacing the precats it came with originally, being a CA car. But I want a replacement for my main cat similar to or better than what it has now.

I'm looking at:

Walker 15622, direct fit replacement -- $110.79 (Rock Auto)

Magnaflow 93441 direct fit (not CA compliant) -- $374.99 (O'Reilly)

Magnaflow 94019 universal -- $126.99 (O'Reilly)

Does anyone have any experience with any of these? Or have any input on the matter? I know cats aren't all created equal but should I just go with the cheapest one and be done with it?

drive it

Are you still in Cali? If so you have to get a 50 state with EO number on it and make sure the EO number is facing down where it can be read. Even tho the vette sits low they did reach under and take a pic to verify the EO number on the smog check.

ThickLizzyVetteswerv

Oh, sorry. No, I'm not in California!

junkyard_dog72

I have the direct fit Magnaflow and am very happy with it. I don’t recall it being that much but I did not buy from O’Reilly. My car is a 1985. Good luck!

mike1111

Metallic Substrate cats can flow more.

Incorvettei

Do you need to have your car inspected? If not why not just replace it with a piece of pipe?

Vets-Vet

I am also interested in the reason for replacement for my own knowledge.
Thanks
Donny

Phobos84

A straight pipe will flow even more.

If you don't live in CA anymore then a straight pipe would be the best option. Much cheaper then a new cat, and will not restrict flow at all. Do you live in an area that requires emission testing and or a visual inspection? Can this be avoided with classic or antique plates?

Even if you have a visual inspection a pipe welded on the inside of the old cat is a far better option.
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mike1111

true. will most likely need a 3 wire O2 sensor. the restriction heats up O2 sensor. sensor needs heat to work. could always just breakup ceramic honeycomb in cat. be the same as straight pipe.

Phobos84

I would put a pipe in it. Having that empty chamber in the exhaust can make them sound pretty bad.

I'm not sure how much that O2 really depends on the cats restriction to build heat. If that were true you would need a three wire O2 for higher flowing mufflers or any other exhaust modification that increased flow. A three wire O2 certainly wouldn't hurt. But I question if it would be necessary.

If you were going that route there is a converter that allows you to use a wide band O2. It has a gauge output and a narrow band output. So it will act as your normal O2 sensor but also give you the wide band signal for a gauge for tuning. Kinda neat but definitely more expensive than a OEM three wire narrow band O2.

ThickLizzyVetteswerv

My car is subject to emissions testing.

Moreover, I like having a clean burning vehicle and the slight hit to performance that a cat brings is perfectly acceptable given the benefits it provides.

I went ahead and ordered the Walker, from Rock Auto. $126 shipped. Should bolt right in.

mike1111

that's a great sounding O2 sensor. I changed to 3 wire O2 sensor to be safe. have headers and free flowing exhaust. was already building an exhaust.

ThickLizzyVetteswerv

Cars are fun.

Phobos84

Wow. Not sure what's up with this but ok. I'll play along. If you're looking for other liberals on this forum you're probably not going to find too many. It must be lonely being a libtard.

Not sure why everything has to go political with you people. Thought we were talking about the exhaust on your car.

ThickLizzyVetteswerv

I was responding to some random post someone made--now deleted--whinging about Biden flying immigrants around the country to fill in voting demographic voids and whatnot...

Nothing to do with anything preceding it. I'm perfectly happy talking about only exhaust.

If you feel comfortable using the term "libtard" as an adult, I'll leave you to it.

'78CorvetteS.A.

"fully propagandized right winger circle jerk"....If you feel comfortable using that terminology as an adult, I'll leave you to it! You talk like that and then call him out for "libtard"....typical!!!

ThickLizzyVetteswerv

The last thing I want to do is tangle with a couple captains of the Harvard debate team so let's move on. I knew I was in trouble when Phobos84 lead with a "you people" statement about a total stranger; no way am I going to risk splintering my bow on the rocks of that intellect. And now that I'm being cited as "typical"--forget it! You guys win and you win big. Bigly.

I'll report on the quality and fit of this Walker 15622 when I have it installed.

Phobos84

🤣 Sometimes I love the Internet.

ThickLizzyVetteswerv

See now that's already two solid things we agree on, either of which could build a lifelong career or obsession or both!

1) Corvettes are awesome

2) The internet is awesome

'78CorvetteS.A.

Says a lot, that you're being a good sport about it!!! I was just trying to point out the irony! I agree, let's focus on the mutual love for corvettes....especially for C4's!!! Seriously though, I respect the ThickLizzy response over the potential ThinLizzy one👍