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92 5.0 cutting CATS off...is this BAD?

  • Thread starter Thread starter kneith
  • Start date Start date Jun 17, 2009
K

kneith

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Jun 5, 2009
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Jun 17, 2009
#1
  • Jun 17, 2009
  • #1
I have a 92 5.0 GT it has brand new flowmaster true dual exhaust from the CATs back............if I cut the CATS off will this hurt the engine?
do the CATS make backpressure for the engine
or is the mufflers enough for that.............
~kelly~
 

FOOT2DFLOOR

New Member
Jan 12, 2004
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Williamston, South Carolina
Jun 17, 2009
#2
  • Jun 17, 2009
  • #2
No it wont hurt anything but your emissions, just make sure that you have the oxygen sensors put back in the new piece of pipe. It will accualy let the motor breathe much better. break out the torch!
 
K

kneith

New Member
Jun 5, 2009
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Jun 17, 2009
#3
  • Jun 17, 2009
  • #3
somebody here at work was telling me that FORD engines need alot of back pressure
is that true.....?
and the other question i have is wheni cut those CATS off
will i notice alittle more sound from the exhaust system?
thanks
 

SVT32VDOHC

waiting for the next hack atta
Founding Member
Nov 22, 2001
3,501
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119
Motor City
Jun 17, 2009
#4
  • Jun 17, 2009
  • #4
Take them off...well, not literally...but let me re-phrase that....Buy an off-road H-pipe.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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Jun 17, 2009
#5
  • Jun 17, 2009
  • #5
Agreed with ^^
If going to the effort, you're better off getting a 2.5" O/R pipe. You can find them [used] locally for not much money (if you dont want to spend 100 bucks on a new one).
 

cardudeusa

Founding Member
Oct 22, 2002
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Home of the Florida Gators!
Jun 17, 2009
#6
  • Jun 17, 2009
  • #6
Also, when you put the off road H on, keep the old one just to have, like if you sell the car or have to pass emissions one day.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,259
17,943
224
Massachusetts
Jun 17, 2009
#7
  • Jun 17, 2009
  • #7
Buy an off-road pipe, don't cut your cats off. You will want to keep the stock H-pipe.


Removing the cats, raises the torque curve slightly and increases top end HP. On a street car, it would be more beneficial to keep the cats as it keeps the torque curve lower and flatter in the usable range for the average street driven car. Most people do it for the sound though, and never take into consideration the change in their powerband. Depending on the car, it can even make you slower (off road exhaust with stock 2.73's and stock 5.0 for example) As long as you don't go with 5" piping from headers back, the curves of the exhaust is more than enough backpressure to promote exhaust scavaging.

if you do cut the cats off, keep them. Don't let the muffler shop take them. Go to local junkyard and ask if they will buy them. Converters contain platnium, and they sell for decent money.
 

Darkwriter77

Resident Ranting Negative Nancy
5 Year Member
Jul 1, 2005
314
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Apache Junction, AZ
Jun 17, 2009
#8
  • Jun 17, 2009
  • #8
Don't cut up a perfectly good stock H-pipe. Buy an off-road H-pipe or X-pipe and save the stocker. You could either sell the stock H-pipe or just kindly donate it to someone like me that needs it for a single-to-dual conversion on an older Fox (like me).

The only time I'd hack up a stock H-pipe to salvage the cats for recycling is if they're so clogged up that they no longer flow at all (they plug up so bad that they glow and/or cause the car to run like poo) or if they're consistently making you fail smog inspection. Otherwise, if they're good, let someone else enjoy them.
 

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
102
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Lancaster, PA
Jun 18, 2009
#9
  • Jun 18, 2009
  • #9
i got a summit brand h pipe for around 120. just as good as any other 200 dollar pipe.
Posted via Mobile Device
 
K

kneith

New Member
Jun 5, 2009
31
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0
Jun 18, 2009
#10
  • Jun 18, 2009
  • #10
thanks guys.............i am not cutting up the stock H-pipe at all........i am keeping it
going to look for an off road h or xpipe used. been looking in my area
milwaukee.........if anyone knows where i can get a decent one i would appreciate it
or what websites to go to.........im on a budget.......thanks all
 

Darkwriter77

Resident Ranting Negative Nancy
5 Year Member
Jul 1, 2005
314
281
134
Apache Junction, AZ
Jun 18, 2009
#11
  • Jun 18, 2009
  • #11
Check your local Craigslist ads ... although stock H-pipes usually seem to crop up for sale way more often than used off-road pipes, no matter where you look.
 
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