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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

4 Cats?

  • Thread starter Thread starter stingeragent
  • Start date Start date Oct 21, 2004

stingeragent

New Member
Oct 16, 2004
33
0
0
Lubbock, Tx
Oct 21, 2004
#1
  • Oct 21, 2004
  • #1
Hi, Just had 40 series flowmasters put on my 94 stang gt, and they aren't very loud at all. The guy at the shop told me it was because I had 4 catalytic converters. I see the 2 ones off the H-Pipe obviously, and are the other 2 those ball looking things that the headers go into? Also, how can I check to make sure they are truly 40 series and not some other series?
 

VibrantRedGT

"STANGNET'S PENGUIN SMACKER"
15 Year Member
Nov 29, 1999
14,679
424
154
Boca Raton, Florida
Oct 21, 2004
#2
  • Oct 21, 2004
  • #2
The ones closest to the front of the car are pre-cats. Change that pipe and it will be loud.
 
W

wytstang

Mustang Master
Mar 14, 2004
4,988
4
78
Summerville,SC missing South Fl. weather :(
Oct 21, 2004
#3
  • Oct 21, 2004
  • #3
Yes the two just after the headers are the other two. For the flow there should be a part# on them grab the # and search the flow web page to see if they match. If you want loud ditch the stock h pipe and replace it with an off road h pipe believe me it will be loud enough then.
 

WhiteDevil

New Member
Feb 4, 2003
2,717
0
0
San Diego
Oct 21, 2004
#4
  • Oct 21, 2004
  • #4
Yeah i just had to put my Stock H back on for smog a couple weeks ago. And damn was it quiet. With any O/R pipe its gonna be nice and loud. And with a catted X or H it will sound great too.
 

Car Nut

Founding Member
Jul 6, 2000
1,176
1
37
Snellville, Georgia (Atlanta area)
Oct 21, 2004
#5
  • Oct 21, 2004
  • #5
My catted X sounds much louder than stock and meatier too. I got the flows first and it was deeper, but it didn't change the volume. Now the volume is turned up a lot, though my neighbors don't seem to mind.

Flows are nice, but better when you can get more air through them. Definitely get something aftermarket for a mid pipe.
 

Car Nut

Founding Member
Jul 6, 2000
1,176
1
37
Snellville, Georgia (Atlanta area)
Oct 21, 2004
#6
  • Oct 21, 2004
  • #6
Didn't see where you lived, but if emissions is a concern.....dont' worry. I passed emissions easily with my catted X.
 

stingeragent

New Member
Oct 16, 2004
33
0
0
Lubbock, Tx
Oct 21, 2004
#7
  • Oct 21, 2004
  • #7
Ah, That explains it then. I was just kinda worried he didn't install em right or something. Would it be cheaper to get a new h-pipe or take off those pre-cats? Also, which setup would give me a better sound, off-road H and the precats, or h/w cats and no pre-cat? One other question, with an off-road H and if I keep the precats, will it pass emissions with just those? And btw, I live in Texas.
 
W

wytstang

Mustang Master
Mar 14, 2004
4,988
4
78
Summerville,SC missing South Fl. weather :(
Oct 21, 2004
#8
  • Oct 21, 2004
  • #8
Aftermarket mid-pipes are sold either with cats(highflow) or no cats at all. None are sold with pre cats just the standard cats(if that makes sense).
 

stingeragent

New Member
Oct 16, 2004
33
0
0
Lubbock, Tx
Oct 22, 2004
#9
  • Oct 22, 2004
  • #9
So basically, I just need to get a new H-Pipe w/ or w/out cats and that will take care of the pre-cats and possibly the normal cats if I go off-road pipe.
 

CManT1914

New Member
Feb 5, 2004
3,172
2
0
Killeen, Texas
Oct 22, 2004
#10
  • Oct 22, 2004
  • #10
stingeragent said:
So basically, I just need to get a new H-Pipe w/ or w/out cats and that will take care of the pre-cats and possibly the normal cats if I go off-road pipe.
Click to expand...

When you buy an aftermarket mid-pipe, it replaces everything between the headers and the mufflers. If you get an o/r pipe, it will not have any cats anywhere. And it will be loud. As for the Flowmasters, when I got mine welded in way back when, they were quiet and crappy. But after a month, they started sounding better and better. I had them on for about 4 months before I did my h-pipe, and they kept getting better. So either give it time, or just throw an o/r h-pipe on and be done with it.
 
C

chrisilversvt

New Member
May 6, 2003
66
0
0
memphis,tn.
Oct 22, 2004
#11
  • Oct 22, 2004
  • #11
seems like throught the years all of my stangs had flowmasters at one time or another,and it did seem like they start sounding better and better the more miles you put on them.....
 
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