02WS6_Publix

Talking with a few of my managers at work today about cars and they brought up how they think I should knock my Catylic converter out of my 2001 Trans Am Ws6. They say it will make my car sound better and recieve better gas mileage.

I have known plenty of people who have done this to their cars...... but I dont know if it's a smart idea for mine, nor do I know how to go about "knocking it out" if I decide I want to. Any advice that you guys have would be great! thanks guys!

z28oc91

iTrader: (1)

i like not having my cat, but i took it off when i did my headers, so i cant really compare to headers with a cat...if you car is stock, i would say dont even bother..plus you gotta remember emision tests where you live, you are going to need a tune and be careful if they do "sniffer tests"

TransAmWS.6

I've never heard of "knocking out" cats, but you can gut them or just bolt-on an O/R Y if you will be able to pass your local emissions. If you just do it, your car will definitely be louder, you will need to tune out your SES light and I highly doubt that you will see any noticeable difference in gas mileage, I sure didn't.

TransAmChris

Its not hard to do it, you will know a noticeable difference, sounds great and you can sell it and get some money.

Ellsworth

Yes, do it, you will like it. Sell the cat for a few bones, and throw it into more mod money for the car

Starz T/A 17

iTrader: (6)

I would say leave it alone. 1. If you knock them out you will throw a SES light and need either O2 sims or a tune to get it off. 2. If will effect the cars tune, so it might hurt your MPG's a little, but def. isnt going to help it (unless the cats are clogged). The only thing they were right about is that it will make your car louder.

With that said to knock them out you have to unbolt them and then shove a long stick through them. Unless you get a ORY pipe.

sepsis

iTrader: (7)

I installed headers and an off road y. I have no cats or rear O2 sensors and now my car runs rich, the gas mileage is bad and the SES light is on. This can all be fixed with a tune though.

I love the way the car sounds and it has much better power.

redtan

iTrader: (5)

You're going to get $60 for a cat, and the cost to cut and weld a straight piece of pipe will probably cost you that or more...so there's no point in doing this for the money to make a small profit...cuz you won't.

You might gain a few hp and make you car slightly louder, but you won't gain any MPGs. If you want a better exhaust tone, get a new muffler. The cat won't do much more than make your car stink.

FinallymyT/A

iTrader: (1)

I agree. Plus what if you move to a different state that has emissions or you resell the car?

That being said, when I was a teenager I did this to my '90 camaro. I would never do it now to my Trans Am. Too much hassle for not enough gain.

BlackScreaminMachine

iTrader: (17)

Ok, back in the 80's and 90's CAT technology was a lot different, much more restrictive and literally you would punch out the material inside the car to "hollow" it out. Work ok back then since there was not much computer control, and in the early 90's ODBI came along and still was not that much of an issue. For reference you could rip the computer out of a 88 Monte SS with out any issues of driving it and the same on 3rd gen TBI/TPI cars, rip the FI off and put a carb on there and run faster...

Come ODBII there comes a few issues. Your car looks at the readings of 2 sets of O2 sensors before the cat (up stream) and after the cat (down stream). Not seeing a different mV reading will make the PCM freak out and willing to wager to better performance or mileage.

The PCM needs to tune out the downstream o2's (See Ready-No Report) so it wont be looking for that reading. Only the first set matters. The "Hallowed out CAT actually creates turbulence since its an expansion and then compression for the exhaust gases. Your better off with a "test pipe" which is removing the car and adding a length of pipe. (see ORY Y Pipe)

Now getting to your stock CAT, those are worth MONEY. There people looking for them all the time, either to sell to salvage or turn cars back to stock. Your moronic friends at work need to not worry about your car.

Like said go find a Off Road Y Pipe and at this point might as well buy headers so your not doing the job twice. Also then you can either buy a "Cat back" system for a better sound and Baffeling or just get a Cut out before the muffler if you want sound/drone.

Latch

iTrader: (8)

First of all your car has two cats. Secondly, just gutting your stock cats isn't going to do much other than make your car smelly. You might pick up a couple HP and make it a little louder, but it's not really worth the trouble of unbolting the exhaust, gutting the material from the converter, and bolting it back up.

Leave it alone until you can afford long tube headers and an ORY. Your stock cats are worth some money so don't gut them.

wicked383lt1

Put some pacesetter LT's on there with a ory and tune it. I promise you'll love it!

BigBirdLS1

If your "CAT" has claws get it out of your T/A ASAP. It will tear up your seats like there is no tomorrow.

In all serious OP the above few posts have all the bases covered.

02WS6_Publix

DANG! now thats what im talking about when it comes to a response to my question. Thanks a lot guys, I really dont think i'm going to mess with anything until i can just buy a Cat Back.... but then the question becomes... CORSA or BORLA? lol

Latch

iTrader: (8)

Between those two, Borla hands down. But as far as catback selection goes, it's largely a matter of personal taste.

Pseudonym

iTrader: (3)

I would say get a set of used pacesetters, ORY and a magnaflow catback

JD_AMG

Have you priced those catbacks yet? Ridiculously expensive, but Corsa is the best sounding catback IMO.
Watch some videos and see which you like before buying anything.

trdavis222

I took mine out and didn't receive any better mileage. We don't have emmisions where I live. It did make it a little bit louder, but not much.

02WS6_Publix

Oh I agree 100%! They are Ridiculously Expensive for sure.... But then again this is my project car and I'm looking to use only the best of the best. (That could change if my wallet stays the same size) lol
In the event I chose to steer away from the CORSA and BORLA brand names what else would you guys recommend looking into?

bamalt1

iTrader: (7)

Go to ls1sounds.com and listen for yourself and find a setup you like and can afford.