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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Oem H-pipe - Replacement

  • Thread starter Thread starter jvmagic
  • Start date Start date Mar 22, 2017
J

jvmagic

New Member
Jul 28, 2015
27
1
3
Mar 22, 2017
#1
  • Mar 22, 2017
  • #1
Hi,

It seems like my oem h-pipe for my 90' 5.0 has gone south. The passenger front converter seems to be the issue. Can I just cut the front converter and replace them? If so, where can I purchase them? What is my best option?

I'm in CA so I need to pass emissions.

Thanks in advance.
 
C

CopNaStang

Member
Aug 19, 2009
20
3
13
Mar 22, 2017
#2
  • Mar 22, 2017
  • #2
Rockauto.com carry stock replacement catted H pipes and catback.
 
J

jvmagic

New Member
Jul 28, 2015
27
1
3
Mar 24, 2017
#3
  • Mar 24, 2017
  • #3
Hi,

My front passenger side catalytic converter is fouled. Can I just replace this with one such as the one in the link below?

https://www.carid.com/1990-ford-mus...alytic-universal-fit-converter-100287344.html - CARB compliant version $78/ea

Can I actually cut the front converters on the h-pipe and pass CA emissions? I read I could just weld the shields to make it look like a 4-cat h-pipe.

Thanks!
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,166
17,860
224
Massachusetts
Mar 24, 2017
#4
  • Mar 24, 2017
  • #4
I think what you linked is a main cat. It may be too large to fit where the precats are.

The first pair of cats are precats. Their role is to be close to the engine warming them up to maximize efficiency. Once warm, the rear, main cats do the bulk of the conversion.

I'd almost be willing to gamble thathollowing out that bad cat would probably still allow you to pass the sniffer. Depends highly on overall tune of car.

What exactly is wrong with the cat?
 
Reactions: jvmagic
J

jvmagic

New Member
Jul 28, 2015
27
1
3
Mar 24, 2017
#5
  • Mar 24, 2017
  • #5
Mustang5L5 said:
I think what you linked is a main cat. It may be too large to fit where the precats are.

The first pair of cats are precats. Their role is to be close to the engine warming them up to maximize efficiency. Once warm, the rear, main cats do the bulk of the conversion.

I'd almost be willing to gamble thathollowing out that bad cat would probably still allow you to pass the sniffer. Depends highly on overall tune of car.

What exactly is wrong with the cat?
Click to expand...

See my thread below:

http://www.allfordmustangs.com/forums/5-0l-tech/1013889-90-mustang-loss-power-runs-rough.html
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,166
17,860
224
Massachusetts
Mar 24, 2017
#6
  • Mar 24, 2017
  • #6
High HC is usually unburned fuel. Generally I'd look to the state of tube, but that banging cat didn't exactly sound healthy if that is the cat making noise.

Did you ever reset timing to 10 degrees?

How hot was the car when you did the test? Ideally drive it on the highway for 30 mins getting it toasty and immediately go get it tested. Do not let it sit, or if it has to, run the engine up to keep it hot.

But, your banging cat does make me suspect it's broken. Does it rattle if you tap with hammer?
 
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