Removing cats

[Dime]

Well, sense I've got to change the oil, I figured I'd remove the cats while I was under the car. I've got Haibeck headers and corsa on my z.

Previous owner gave me a a set of pipes to replace were the catalytic converters usually are. I was wondering if removing the cats could cause any harm to the car, or would I only get a happier car with more noise and hp?:dancing

[Kevin]

shouldn't be an issue

[efnfast]

If you've got a M.H. chip, he can reprogram for a little more hp without the cat. He'll change the air/fuel ratio. We like more hp. -Steve

Assuming you're taking inspection issues into consideration.

[VetteMed]

Removing the cats will probably change the tone of the exhaust a bit (louder, usually), and the exhaust will be a bit smellier than you're probably used to.

[secondchance]

Removing the cats will probably change the tone of the exhaust a bit (louder, usually), and the exhaust will be a bit smellier than you're probably used to.

And it's a good smell. :cheers:

[VetteMed]

And it's a good smell. :cheers:

No argument from me on that one!:cheers:

[Dime]

Assuming you're taking inspection issues into consideration.

This is Mississippi, I have no idea what you're talking about. :sign10:

More power, more smell, more noise, all sounds good to me.

[rhipsher]

For us guys with 90's it's only a little more than two years and we will be exempt from emissions testing. And on that day the cats are coming off. Oh yeah!

[secondchance]

Also, I am inclined to believe the cat removal also dropped my coolant temp.I am not positive because I also installed a new 180 thermostat w/ one 1/8" hole. Now in cruise in 90+ temp day the Z runs at about 200. Even in stop and go traffic in90+ day w/ AC running the temp stays around 210 to 212.

[RICKYRJ1]

I have been running with no cats for about 3yrs now. Marc H. did my car, he said about a 4hp gain. I also have zero issue with any kind of foul odors except burning rubber :-D

[secondchance]

I have been running with no cats for about 3yrs now. Marc H. did my car, he said about a 4hp gain. I also have zero issue with any kind of foul odors except burning rubber :-D

Like I said - it's a good smell - it smells like... victory!

[Dime]

I have been running with no cats for about 3yrs now. Marc H. did my car, he said about a 4hp gain. I also have zero issue with any kind of foul odors except burning rubber :-D

Yep, just got an email from Marc. He said around 3hp or so, and around 25% louder. Thanks for the help all.

[Kevin]

but with the corsa, still no drone.

[VetteMed]

but with the corsa, still no drone.

Agreed, same here. Headers, no cats, Corsa, and very pleasant at cruise.

[RICKYRJ1]

but with the corsa, still no drone.

I have corsa no drone :saluting:

[CamP]

For us guys with 90's it's only a little more than two years and we will be exempt from emissions testing. And on that day the cats are coming off. Oh yeah!

I am looking forward to my '90 turning 25yo, getting Texas antique plates, and saying good-by to annual inspections.

In the meantime, there's a loop hole around emissions testing in Texas. If your car is driven and stored less than 60 days a year in a emissions testing county, you can obtain a safety-only inspection from a non-emissions county. This is the case even if the car is registered in an emissions testing county. You just sign a affidavit, and you're off. The best part is it's just $14.

[Kevin]

my car hasn't been smoged sine 1999, and it was exempt before that

[Bob Eyres]

I took the cats off in 1995, and it still passed the smog test. I've got headers, B&B 3" exhaust, and the sound is pretty wicked.

If you've got a lot of miles on those cats, you may experience more of a horsepower jump than you expect if you take them off, because of particulate buildup in the cats restricting the exhaust flow.

You've got a white car like mine, and might also see unburnt hydrocarbon stain on your rear end over time. (I hate it when that happens :redface:).

So, make sure you keep your big white butt clean and you'll be good to go.:bootyshak :dancing:dancing