Hey i was wondering if I remove my Cat and replace it with regular 2.25" Exhaust tubing will this improve power at all? Also, after an extended period of time will this procedure ruin my exaust valves, im just not sure exactly how much backpressure cats produce? Also if its a @!#$ idea, what other options do I have?

removing your cat will greatly reduce back pressure, however it also greatly reduces the legality of the car for street use. I would probably recomend a high flow cat for it instead, that way your legal, you still have some backpressure from it, but reduced. Catco makes some nice direct fit replacements for all engines in 3rd gen. you might have to do some searching for them, but I found the fully stainless direct fit for my 01 2200 for around $180. You could also do a universl cat for much less if your on a budget.

Im not to worried about the legality of it, any thoughts on the exhaust valves or power increase/decrease?

youll have less at bottom end, more at top end. Thats how the backpressure game works, but it will set you MIL light off, and youll see a lot of carbon around the back bumper. Overall, you would be gaining power, but not a while heck of a lot or anything.

MIL Light?

MIL = Malfunction Indicator Lamp - aka - check engine light

MIL being the technical term used by manufacturers & what you see if you plug in a scan tool...etc.

K and about the valve damage?

I dont know why it would, Im not the person to ask about that. What I do know, is if the computer knows your cats gone, it will affect how much fuel your engine gets, maybe trying to lean things out if your reading rich after the cat...so you might have some problems there, unless you get an o2 fakey....but valve damage from removing cat doesnt seem to be a problem, but I would try to get someone elses advice on that too.

first of all not all states require a cat..so legal issues depend on location...and about the valves..i have a friend with no cat on his HO quad and he doesnt have valve proplems...infact he recommends the idea..but they are right about the light staying on.unless you can get some kind of simulator

i had no cat on my 89 camaro when i had it....lost power on the bottom but gained it up top...andn o damage to the valves. honestly im not sure how it could damage the valves.

I have yet to see a ECO or LD9 run right without a CAT....if they either didn't delete the second O2 with HPTuners, or used some kind of simulator.



PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO

I have a 95 2.2 so there is no 02 sensor near the cat, is this gunna still flick the check engine light?

your power gains are noticable, I just removed mine recently, the only problem is it sounds terrible. I am putting a resonator on it to tone it down a little bit and get rid of the ricer effect.


Veritas Aequitas

K well i suppose its time to get out the hacksaw and some clamps

removing the cat sees does nothing.... newer cats like the ones in our cars are honeycomb atyle and flow very well removing the cat will only hurt our environment

i thought removing cats was a federal offense? though i did drive without them on my car because i was broke and it clogged. now i have a hi flow and i had the exhaust ran from manifold back to tip, all custom. but though a state might not require it, i believe federal does. someone correct me if i am wrong please.

Cat's are required my law everywhere if the car came stock with one, muffler laws vary frome state to state. Magnaflow makes good high flow cats for around $50 to $60, RKSport sells O2 simulator moduals for our cars part # 02094035 for $67. Your best bet is to run a cat, it will make sure you have enough backpressure for your car to run right, and your car will be way to loud if you modify the exaust any further. I had a streight pipe (no cat) and a cherry bomb glass pack on my 2nd gen 2.0 sunbird, it ran good but had no low end power at all, just a lot of high end, and I got pulled over all the time, plus it was OBD1 (no second O2 sensor). I wouldn't recomend removing one on an OBD2 car.

Theres only one O2 sensor on my car at the manifold, its a 95 2.2L , And I live in canada so we have no laws, and thats all The info i need boys and girls Thanks for your help

Oh just for an update to anyone thinking of removing it on a 95-99 2.2 (I dont know really about the others) I wouldnt. I just finished removing it the other day and now it sounds terrible, bit of a gain in power through mid-top rpms though