hi, everyone i've been thinking about doing some modifications to my monte's exhaust system. I dont want to do anything too serious that would cost alot of money since i am a student. I was wondering if maybe it was possible to remove some stock features that will increase the flow and improve the sound. would remoivng the cat and resonator be enough? would getting rid of these features mess with the cars computer system (o2 sensors)? would it sound good to straight pipe everything up to the mufflers but leave the mufflers? or maybe leave everything and remove the mufflers?

Im just wondering if doing any of this would make improvement and sound good or be a waste of time. Please give me some suggestions or anything that has worked for you with your monte carlo.

-thanks

 

what year and what motor? i took the muffler on my 01 3.4L and did a Y pipe. cost about 180$ with SS 3.5in weld on tips. sounds great IMO

 

its a 2001 ss, it has the 3.8

thanks for your input

 

Get a downpipe with U-bend delete and highflow cat from ZZP. All bolt on.. I just did it to my 01 monte ss

 

I agree with BlueSS, ZZP 2.5" DP with high flow cat. I also vote resonator delete (that's how my Monte is).
Some say the exhaust is "droney" with out the res, I notice very little change (sounds a little tinny, but I'm OK with it).

Any cat change may result in an erroneous Check Engine code. I believe it's a P0420 code. Fixes for that are:
1 - use the spark plug non-fouler method to space the O2 out of the exhaust stream.
2 - have the code permanently deleted from the PCM with a tune.

 

Deff downpipe & u bend delete ive res delete my car & it sounds amazing im getting ready to put borla mufflers on it

 

alright, thanks everyone for your ideas. I guess I have some thinking to do. thanks again

 

I was thinking of removing the cat along with the u-pipe and the resonator and in its place putting a straight pipe that leads to the rest of the exhaust. I would be leaving the existing mufflers but one big problem remains. By removing the cat, I would be removing the o2 sensor which would mean an engine code. What are some easy ways of getting rid of the code?

What is the spark plug non-fouler method? and how can I get the code simply removed?

 

This may sound dumb but its a shot in the dark. What if the o2 sensor was left outside of the exhaust system so it would be sensing the air not the exhaust. since there are no emissions would a code still come up?

 

One, I would NOT remove the cat unless you are in a location where you do NOT need to do any emissions tests.

You can still have an O2 bung put into straight pipe.

I would NOT leave the O2 sensor hanging or tied down, get it screwed into a bung. The spark plug non-fouler trick is a simple idea (it's what I was going to do if I needed to worry about an engine code before I had the I had the code permanently deleted from my PCM, but I never had to worry about it). Basically, in the Dorman help rack at the parts store is a thing called a spark plug non-fouler. You bore one out to fit the probe of the O2 sensor. You use it as a spacer (I've read it may take two total to may it work). It spaces the O2 out of the exhaust stream and it no longer has a problem and does not trip a code.
Look it up on the Internet. Many people with high flow cats on just about ANY make/model car have noted success with this method.