I plan on doing it this weekend... I'll let you know how it goes.

 

Dude, I would so love to gut my mom's cats. Don't think that would go over so well though!

 

i think for some states you would have to replace them with stock cats.

 

[quote=zinn,February 22, 2005, 10:43 PM]
i think for some states you would have to replace them with stock cats.

Yeah, if you were "forced" to put cats back on before the car is five years old or has 50,000 miles on it, you will prolly have to put the stock ones back on....may be best to error on the side of caution, money wise.

 

It doesn't matter to the state what kind of cats you have on your car (if your state checks emissions), it only matters if you car passes the test....and w/out cats it is highly unlikely, this mod isn't for those who live in areas that have emission tests!!!

 

alright service engine light has finally come on, but still no difference in noticeable power/mpg.
will take care of w/ a re-flash soon.

 

So, when you flash the computer, what do you basically tell it? That you have no cats? And do you think once you reflash, you'll get more power?

 

once you reflash it, it tells the computer to disregard the rear O2 sensors, which in turn makes the computer think everything is OK...so the computer isn't trying to balance out the mixture to compensate for the rear O2 sensors readings.

 

I gutted out my cats yesterday. I love the sound... definitely a lot louder and has a deeper growl. Only bad thing would be the smell. The exhaust smell is a good bit worse. But no regrets. Sounds so much better and it has to add at least 5 HP even though I can't really feel a difference. Especially once I tell the computer that I don't have cats.

 

If my understanding is correct (This IS a new ECU after all!), the computer does NOT make any adjustments based on the rear O2 sensors readings. None. All it does is use the rear O2 sensors to verify that the cat is doing it's job and cleaning up the exhaust like it should. All the vehicle fueling adjustments are made based on the front sensors only. The only this that happens when the ECU is unhappy with the rear readings is it sets a code and turns on the "check engine" light for you. But turning them off completely is still the way to go...

 

I think I would pop for the bassain low restriction cats.No need to put all that crap in the air.

 

You are correct sir!

 

As long as only a few of us do it, it's not that bad for the environment. So few people are going to actually go to all the trouble to hollow out their stock cats (which by the way, is the exact same thing as getting an off-road mid-pipe). High flow cats will get you more airflow and a better sound, but there's no sound like having no cats at all. I would go as far as to say it is twice as loud as with my Magnaflows (not the packs) before gutting the cats. It sounds like I put long-tube headers on. This is how a Mustang should sound. In a couple years when I get some new headers, this car will sound really mean.

 

can you guys answer me a few ?s please....i just ordered the magnaflow cat back system today...i was going to order the magnaflow thru-x hi flow x pipe....will i get any kind of check engine light...will my 02 senors hook up to my new exhaust sytem...will any kind of problems show up at all....in ohio there is emision testing every 2 years...hopefully in 2 years i will not have to put the old system back on to pass my e-check...thanks
jerry

 

You shouldn't have any problems with the computer if you install an x-pipe with high flow cats. It should come with the bungs to hook your o2 sensors into and the computer should recognize them. I think you'll be fine. I'm sure my check engine light will be coming on soon because I don' have cats at all. You will probably have to put your stock mid-pipe back on every year for testing though.

 

Good to hear someone else is brave enough to start modding the mustang and save some money at the same time...(Acadian)
-It wasn't that hard, was it? and saved probably $200+

 

My only problem was not having long enough needle-nose plyers to get the wire mesh out of the cats. I rigged up a metal skewer, bent the tip into a curve, and yanked it out. So, it probably took me a bit longer than you, but not more than an hour and a half or so. Well worth the money I saved. And I am now driving around with the radio off... I love the sound of the exhaust. Thanks again!

 

Yeah, I know the feeling about turning down the radio and riding w/ the windows down. I noticed my mpg dropped to, but it wasn't from the hollowed out cats, just from my foot pressing on the pedal a little harder every shift...LOL.

 

I can't tell you how many people have stopped me in parking lots, and been like "darn, is that the way they sound from the factory? That's how a Mustang should sound." From teenagers to older men.

 

You definitely get more heads turning from people who just hear the rumble of the car when you accelerate. I've definitely been hitting the pedal a lot more after gutting the cats. Hopefully, I'll get back to normal driving soon.