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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

5.0 W/O cats?

  • Thread starter Thread starter keepinitril
  • Start date Start date Apr 24, 2009

keepinitril

Member
Mar 24, 2009
102
1
18
Anaheim Hills
Apr 24, 2009
#1
  • Apr 24, 2009
  • #1
how much power can the 5.0 dish out with out the 4 cats and 2 mufflers? I was fixing the side mould leading to the tire, and I saw that I had 4 cats, then I got to wondering.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,216
17,899
224
Massachusetts
Apr 24, 2009
#2
  • Apr 24, 2009
  • #2
Cat's aren't all that restrictive

Replace them with a modern high-flow catted pipe and you might see a few more.

Taking the cats off moves the torque curve up slightly. You gain top end HP but the shift in the torque curve might hurt performance because you've lost your low end nut.
 
G

GTOreturns

Well-Known Member
Oct 1, 2003
51
17
59
West Coast Best Coast
Apr 24, 2009
#3
  • Apr 24, 2009
  • #3
keepinitril said:
how much power can the 5.0 dish out with out the 4 cats and 2 mufflers? I was fixing the side mould leading to the tire, and I saw that I had 4 cats, then I got to wondering.
Click to expand...

Depends, if there healthy and not clogged it will take away top end power, but delivers good bottom end torque.
 

Dizzy_ax

Member
Mar 26, 2008
93
1
8
Troutdale Oregon
Apr 24, 2009
#4
  • Apr 24, 2009
  • #4
i got rid of them. they suck! and our four cats are really small...i went with two high flow but then had trouble passing emissions. could of been the mods and the tune.

Im going to look through my 3.73 thread and see if removing them did anything to my E/T.
 
G

GTOreturns

Well-Known Member
Oct 1, 2003
51
17
59
West Coast Best Coast
Apr 24, 2009
#5
  • Apr 24, 2009
  • #5
Me too! (Had trouble passing emissions) Keep your stock h-pipe for inspection.
 

Dizzy_ax

Member
Mar 26, 2008
93
1
8
Troutdale Oregon
Apr 24, 2009
#6
  • Apr 24, 2009
  • #6
I just went in with five different tunes and got it to pass on the third tune! they thought i was weird going out shutting my car off and coming back in lol. i went from the 14.4-14.5 to a 14.1 but i did a few things with getting rid of the cats. Sounds better too ;p

Then went back out with the short shifter and shifting right, thats when i hit 13.8
 

LiquidGT

Member
Oct 8, 2007
368
0
16
Near STL hell
Apr 24, 2009
#7
  • Apr 24, 2009
  • #7
I passed with my high flow cats and no thermactor system, sometimes I wonder if the emissions guys didnt care because it was my cars' final emissions test. Well I did have a freshened modded up engine and a buggy barely idling "tune"; so IDK.
 

strtrcr50

New Member
Jun 21, 2006
0
4
0
Previously from Dirty Jerzey exit 7a
Apr 24, 2009
#8
  • Apr 24, 2009
  • #8
I passed NJ emissions with flying colors with a pypes catted x..
 
G

GTOreturns

Well-Known Member
Oct 1, 2003
51
17
59
West Coast Best Coast
Apr 24, 2009
#9
  • Apr 24, 2009
  • #9
strtrcr50 said:
I passed NJ emissions with flying colors with a pypes catted x..
Click to expand...

 
M

Mint88

New Member
Apr 21, 2009
14
0
2
Apr 25, 2009
#10
  • Apr 25, 2009
  • #10
I have an off road h pipe with 2 chamber flows, and in between shifts at high rpms it afterfires really loud! Sounds like a gunshot!
 
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