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RobinHood
04-08-08, 08:28 PM
I have a question regarding catless x pipes. Since you eliminate the o2 sensor and you get it re-tuned it just puts in set parameters in the ECM right? If you do that then it doesn't adjust for elevation or something like that?

I have a feeling I'm mixing that up with a MAF.

BurnTire
04-08-08, 08:30 PM
I have a question regarding catless x pipes. Since you eliminate the o2 sensor and you get it re-tuned it just puts in set parameters in the ECM right? If you do that then it doesn't adjust for elevation or something like that?

I have a feeling I'm mixing that up with a MAF.

Ok what year of car are we talking about?

RobinHood
04-08-08, 08:35 PM
04 Gt

BurnTire
04-08-08, 08:39 PM
04 Gt

You don't eliminate O2's. The front O2's are required for the car to run. The rear O2's tell the computer the cats are working correctly.

The rear two can be turned off in the tune with no negative effect to drivablility.

RobinHood
04-08-08, 08:41 PM
You don't eliminate O2's. The front O2's are required for the car to run. The rear O2's tell the computer the cats and front two are working correctly.

The rear two can be turned off in the tune with no negative effect to drivablility.

oh. awesome.

forget the catted x pipe then.

BurnTire
04-08-08, 08:43 PM
oh. awesome.

forget the catted x pipe then.

I have a catted x pipe with the rear O2's turned off.

I had a cat less pipe at one time, but couldn't stand the fumes the car produced.

My car ran no better in the 1/4 mile without cats.

RobinHood
04-08-08, 08:45 PM
so does it make a difference with it turned off and still having them?

BurnTire
04-08-08, 08:47 PM
so does it make a difference with it turned off and still having them?

Yes and No the rear O2's serve no driveablity function. The will only throw a code if they sense the cats are not working efficiently.

You want to turn the rears off without cats.

With cats you can have them on or off.

RobinHood
04-08-08, 08:52 PM
Yes and No the rear O2's serve no driveablity function. The will only throw a code if they sense the cats are not working efficiently.

You want to turn the rears off without cats.

With cats you can have them on or off.

so in your opinion what should i get.

BurnTire
04-08-08, 08:56 PM
so in your opinion what should i get.

Well it is up to you. I have a good sense of smell. LOL

I personally like a set of high flow cats for a street car.

You are not going to see a big power gain if any cat less.

I have a magnaflow catted x pipe and it is a nice unit.

RobinHood
04-08-08, 08:57 PM
Well it is up to you. I have a good sense of smell. LOL

I personally like a set of high flow cats for a street car.

You are not going to see a big power gain if any cat less.

I have a magnaflow catted x pipe and it is a nice unit.
sounds good.

thanks for the help!

BLK03SVT
04-08-08, 09:14 PM
Yes, I can tell you first-hand that without cats it is possible to get high while driving in stop and go traffic with the top down..LOL

GAZ
11-08-08, 11:33 AM
Yes and No the rear O2's serve no driveablity function. The will only throw a code if they sense the cats are not working efficiently.

You want to turn the rears off without cats.

With cats you can have them on or off.

So the magnaflow catted x pipe has a bung for the rear o2 sensor? Is there an advantage to running with the rears on or off? Also I guess the front ones are before the x Pipes.

BurnTire
11-08-08, 11:49 AM
So the magnaflow catted x pipe has a bung for the rear o2 sensor? Is there an advantage to running with the rears on or off? Also I guess the front ones are before the x Pipes.

Yes there is a bung for the rears

The fronts are before the x prior to the cats.

The rears only give the computer info and do not affect drivabilty if turned off in the tune.

If you have a stock tune you will need to run the rears. You will also need the 02 extender harness because the catted x rear bungs are further back than the stockers and the wires will not reach.