are there any o2 sesors connected to the back 2 cats or are they just on the front ones? could go out and look but it's just too cold right now.

 

You should have two before the cats and two after on a '97. Is a little cold tonight in Dixie!

 

say i got a saw zaw and cut the back cats off =) what could i expect computer wise? what would it do? moreless just need to know what to do with the sesors after the cats come off, without messing up anything.

 

You can get 02 eliminators at Summit Racing or Jegs and if you don't the CEL will be on and your fuel mileage will drop.

 

thats what i heard. sensors blow!if it didnt have em i would cut it all out with a saw zaw run staight headers and sound like a log truck coming down the road. they dont check emissions around here, and i'm gonna cut the cats off. just wanna know the cheepest way to do it? one place said the rear cats would be fine to cut cause the front sensors contol the gas oil mixture?

 

Wow. If you think this is true, then your truck must be a 2-stroke, lol.

Cutting off cats is Illegal, Federally, regardless of your area's emmissions policies.

You will NOT gain any performance, and there are other, Legal ways to make your truck louder.

You need to retain the front O2's to control air-fuels. You can lose the rear cats IF you install 2 high-flows in place of the 4 you have now. The rear sensors can stay without bothering anything - they are cat monitors.

Be responsible, please; we already have enough redneck hillybilly peckerheads doing this with no clue and no conscience.....

 

been watching this thread and had a question.

Has anyone experienced o2 sensor failure after replacing the four cats with the 2 high flows? i know that there will be a bunch of welding going on down there and didnt know if this was a situation where o2 sensors typically bite the dust.

also, i currently run to 40 flows exiting in front of the rt rear tire. will be installing to high flow mag cats in place of four stock soon. if there are any comments about this set up i would be glad to hear them.

thanks!

 

"Sawsall"

 

henry,

i have had my hi-flow maggies installed for 10k and no CEL light or problems. i am running the original sensors in the back as well. the front are new ones, also no problems there.

 

bluedevil. you can buy high flow cats at autozone for like 50 bucks, your best bet for your truck to run right and be loud would be to get those, clamp them in place of your old 4 leave the sensors just add pipe, clamp it in then dump it after your cab or throw on a 10 series flowmaster and dump it, or have someone weld in an x pipe get rid of the y then dump it or put on 2 10 series and dump them.
if you dont care about your truck, cut out the cats and put some pipe in place then add some mechanical cut outs before the y. it will be loud. but also illegal and not great for the truck.
both ways are the cheap way to do it. when i was in highschool i spent a lot of time with a sawsall and my first welder. just make it work, its a right if its ghetto-rigged as long as it works.

 

When replacing the 02 sensors, should you return the PCM to a stock tune if you have a tuner? I know you should disconnect the battery.

Thanks!

02 F150 Super Crew Lariat FX4 White & Silver
5.4 /w Roush Cold Air Intake & K&N filter
3.55 LS
Flowmaster Cat Back
JBA Silver Cat4ward Headers
Rancho RSX's
Rancho Steering Stablizer
Hellwig Rear Anti Sway Bar
Lightning Tails
Outland Sport Bumper Guard
Hella 550's
Silverstars
Superchips 9100 Micro Tuner c/o Troyer Performance
Underdrive Pullies c/o Troyer Performance
Mag-Hytec Trans Pan & Rear Cover

 

i did not have a tuner when i got the work done, o2 and highflows, but it makes sense. it wouldnt hurt and you can put it back right after.