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  • 1996 - 2004 SN95 Mustang -General/Talk-
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Do I need new headers?

  • Thread starter Thread starter Lannoir
  • Start date Start date Mar 31, 2020
L

Lannoir

New Member
Mar 31, 2020
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0
1
Cumming
Mar 31, 2020
#1
  • Mar 31, 2020
  • #1
Hey guys so I have a 2002 v6 automatic, and I have a problem. Because of a problem with my cats getting clogged I need a new exhaust, but I need to know like in the next 24 hours: can I bolt 2.5” Mac off road h pipe to the stock headers on my v6? Because I’m out a car and a way to work until I get this fixed, so I need answers ASAP please. And I can’t afford new headers so that’s out of the question...????? Please help someone
 

08GT500

5 Year Member
Jul 12, 2018
918
140
63
Massachusetts
Apr 3, 2020
#2
  • Apr 3, 2020
  • #2
Hi,
Happy to help, need more information.
1) Are you running the vehicle’s stock exhaust Manifolds, or aftermarket shorty, or long-tubular Headers (if so, by what MFG?).
2) Was the MAC catless H pipe you bought intended for usage with stock exhaust manifolds, or long tubular headers(Part #?).
3) Car has/has the stock Y exhaust system, or has been modified to run dual exhaust, front to back?

-Usually, shorty headers, like stock manifolds, bolt up to a stock-type exhaust system (ball & socket (2) bolt flange design w/downpipes) without modification.
- Long tube headers will not bolt up to the vehicle’s stock exhaust systems without pipe length modification in addition to adding (3) bolt header collector flanges.
Either are easily converted in a pinch with an angle grinder, MIG welder, few pieces of pipe, and/or collectors.
Best!
-John
 
L

Lannoir

New Member
Mar 31, 2020
2
0
1
Cumming
Apr 3, 2020
#3
  • Apr 3, 2020
  • #3
08GT500 said:
Hi,
Happy to help, need more information.
1) Are you running the vehicle’s stock exhaust Manifolds, or aftermarket shorty, or long-tubular Headers (if so, by what MFG?).
2) Was the MAC catless H pipe you bought intended for usage with stock exhaust manifolds, or long tubular headers(Part #?).
3) Car has/has the stock Y exhaust system, or has been modified to run dual exhaust, front to back?

-Usually, shorty headers, like stock manifolds, bolt up to a stock-type exhaust system (ball & socket (2) bolt flange design w/downpipes) without modification.
- Long tube headers will not bolt up to the vehicle’s stock exhaust systems without pipe length modification in addition to adding (3) bolt header collector flanges.
Either are easily converted in a pinch with an angle grinder, MIG welder, few pieces of pipe, and/or collectors.
Best!
-John
Click to expand...
I still have the stock manifolds on her, and she still has the stock y pipe. The h pipe I bought said it works with aftermarket shorty headers or the stock manifolds, but I wanted to make sure because the shorty headers it said it worked with were 2.5” but the stock pipe is 2.25” so I assumed that the stock manifolds came out to 2.25 collectors, which is what has been tripping up my brain. Just wanted to make sure she won’t need much modification. Also I now have a second question... because of legal reasons, I have decided to fab in two slp high flow cats into the h pipe. Will a v6 with true duals, slp high flow cats on an h pipe, and flowmaster super tens still be really, really shockingly loud? Because I know it would be if it was catless but I wanted to make sure I won’t lose too much volume with the high flow cats, because I really want her to be attention-grabbing....? Thank you for all your help bro.
 

kiddiccarus

The first widely accepted Tranny
20+ Year Stangneter
Dec 24, 2003
1,789
1,051
143
30 Mins from a Ragged GT
Apr 3, 2020
#4
  • Apr 3, 2020
  • #4
Look at my build thread. I have installed:

Shorty Headers
Custom X Pipe
440 Flowmaster American Thunder (V8 Version) Dual 2.5 inch

This is on my Convertible and is TOO loud for what I intended, but its on there so It will remain

Progress Thread - 1995 3.8L Vert (2002 3.8L Dual Port Engine)

Mods: (Will Edit List As Things Added/Completed) Last Update 30 January 2020 The old Engine (95 3.8l Single Port) is for sale, it is functional, has manifolds for the 2002 engine p.m. me if you want to talk Engine: Began as Bone Stock 3.8 Single Port @ 145 HP (Book Math For Current State...
www.stangnet.com
 

08GT500

5 Year Member
Jul 12, 2018
918
140
63
Massachusetts
Apr 3, 2020
#5
  • Apr 3, 2020
  • #5
Hi,
IMO, Best thing to do is pick up the phone & call the Mfg.& ask if uncertainty abounds in the future vs.stressing over it.
Cat’s, smart move! SLP Cat’s won’t quite have the effect that OE Cat’s did on sound suppression, should give a deeper note & they’ll still hear you coming.
Most importantly, you’ll be legal & not spewing Nox, CO, and HCs everywhere.
Good luck!
-John
 
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