High Flow Cat or no Cat?
#11
My stock cat pooched out maybe 10-15 thou miles ago and was replaced by a stock one as far as i believe by a local exhaust shop. I was thinking about getting a PCM from Overkill but I heard ZZP was the best? I would love to support a Canadian company, so if you guys haven't had any problems with the OVerkill Pcm maybe that might be the best route? Is this the correct downpipe for my application? ZZ Performance
Will i need the front and rear gaskets as well? I am just not sure whether to run a cat or not? I am not worried at all about the emission laws, its just whether it will run better or not, or will I lose fuel economy? Also I do not want to throw any codes but overkill can take those codes out, not?
Thanks so much for the replies guys, I really appreciate the help.
-Devin
Will i need the front and rear gaskets as well? I am just not sure whether to run a cat or not? I am not worried at all about the emission laws, its just whether it will run better or not, or will I lose fuel economy? Also I do not want to throw any codes but overkill can take those codes out, not?
Thanks so much for the replies guys, I really appreciate the help.
-Devin
#12
Join Date: Apr 2010
Location: Mentor, Ohio
Posts: 12,195
The high flow cat will not hurt fuel economy (if anything, it may improve it, as a car that run more efficiently wastes less fuel).
As far as gaskets, there *might* be a slim chance you could re-use your old gaskets (my guess is once you seperate the items sandwiching the gaskets, they will be shot). Even if you could re-use them, I would highly advise against it. For how little new ones cost, it's not worth having to do the job a second time because you wanted to cheap out on the gaskets.
As far as throwing codes, I have had my ZZP downpipe and High Flow CAT in my Monte for about 5,000 miles, no code. BUT, I don't drive my Monte as a daily driver and I know others who do and have seen codes pop up in about a month's time. Originally, I was not planning to get my PCM re-programmed and I found info on using a Spark Plug Anti-Fouler to move the rear O2 sensor out of the exhaust stream to resolve the code (if you search the Internet, that is the cheap-o fix for anyone with a high flow cat no matter the make/model of the car). But at this point, I will be getting my PCM re-tuned and I will have this issue addressed at that time (all they do is basically remove the PCM's programming to know of throwing that code).
As far as gaskets, there *might* be a slim chance you could re-use your old gaskets (my guess is once you seperate the items sandwiching the gaskets, they will be shot). Even if you could re-use them, I would highly advise against it. For how little new ones cost, it's not worth having to do the job a second time because you wanted to cheap out on the gaskets.
As far as throwing codes, I have had my ZZP downpipe and High Flow CAT in my Monte for about 5,000 miles, no code. BUT, I don't drive my Monte as a daily driver and I know others who do and have seen codes pop up in about a month's time. Originally, I was not planning to get my PCM re-programmed and I found info on using a Spark Plug Anti-Fouler to move the rear O2 sensor out of the exhaust stream to resolve the code (if you search the Internet, that is the cheap-o fix for anyone with a high flow cat no matter the make/model of the car). But at this point, I will be getting my PCM re-tuned and I will have this issue addressed at that time (all they do is basically remove the PCM's programming to know of throwing that code).
#13
Mine through the code P040 almost immediately after I did the u-bend delete and installed the Magnaflow cat... I had Will from Overkill Motorsports tune my PCM and delete all related codes... Now she runs great and my dash has no annoying check engine lights on...
#15
I would say after I installed My 2.5" Cattless Downpipe It only took 2 Blocks befor Check engine Light came on..For Me The engine light doesnt bother me.. How I sit in Monte pritty much the steering wheel blocks the light.. and eventully the light will burn out right :P HAHA Ive had no issues once downpipe was installed runs great SOUNDS great.. CANT wait to hear it SOON maybe NEXT WEEK I CAN DRIVE IT!!!
Yea I think its time for a PCM tune LOL....
Yea I think its time for a PCM tune LOL....
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