Dumb exhaust questions

Vigilante

Active Member
Established Member
Joined
May 17, 2007
Messages
1,159
Location
Phoenix
Good Afternoon!

I accidentally messed up and bought 3" headers and mid pipe for my build when I meant 2.5"

Two questions:

One, can I fudge the stock catback to merge? At this point I'm just trying to get it all back together as cheap as possible ?(long explanation coming in my future "finally finished" thread)

Two, when I have the money I wanted to go with the borla #14445 as my catback, except that is only in 2.5" so I would need to build this kit from pieces. I can buy the mufflers from borla no problem, but Flowmaster makes "universal kits" are these worth it? I could just assemble what I need and then have a shop weld it together yes?
 

TaraFirma

Well-Known Member
Established Member
Joined
Apr 20, 2007
Messages
1,721
Location
NW Austin/Central Texas
If you have a really good fabrication skills and are comfortable piecing together an exhaust system, I said go for it. If not, it’s really not worth the headaches to try to piece something together and then trust that somebody else will be able to weld/assemble it correctly.
 

Mojo88

"Hammer" Time
Established Member
Joined
Jan 30, 2017
Messages
1,319
Location
RI
I totally concur with @TaraFirma.

If you absolutely had to work with existing parts, you could fudge it together using simple, readily-available 3" to 2.5" reducers, but I would swap the parts out for the right ones. If you did decide to go with reducers, I would shop online for stainless steel pieces, grade 304 (not 409). The reducers from local auto store would work, but they would rust quickly.

You would want something that looks like this:
reducer.jpg


Again, I would only do the reducers as a last resort. Much better to get the correct 2.5" parts.
 
Last edited:

2DXTRM

Pushrod 5.0
Established Member
Joined
Sep 17, 2008
Messages
2,422
Location
Some time zone
Good Afternoon!

I accidentally messed up and bought 3" headers and mid pipe for my build when I meant 2.5"

Two questions:

One, can I fudge the stock catback to merge? At this point I'm just trying to get it all back together as cheap as possible ?(long explanation coming in my future "finally finished" thread)

Two, when I have the money I wanted to go with the borla #14445 as my catback, except that is only in 2.5" so I would need to build this kit from pieces. I can buy the mufflers from borla no problem, but Flowmaster makes "universal kits" are these worth it? I could just assemble what I need and then have a shop weld it together yes?


Which brand headers and midpipe? Most pipes are able to bolt up to stock or stock type exhaust systems with their ball/socket flanges.
 

milktasd2

Active Member
Established Member
Joined
May 2, 2004
Messages
956
Location
Jackson,Ms
I would add reducers to the catback. That’s essentially what I did. Running steam rollers in the back, I ordered a 2.5” catback and had a shop reduce my 3” mid pipe to meet the catback.
 
Last edited:

Mojo88

"Hammer" Time
Established Member
Joined
Jan 30, 2017
Messages
1,319
Location
RI
Please don't use those redneck reducers. Use a formed transition instead. Those cheap stepped trash parts are for the poors.

This is an example of what you want to use:
2.5" to 3" 304 Stainless Steel Formed Transition– Motion Raceworks

In his original post, he's using words like "fudge it together" and "cheap as possible". I totally concur, those parts like you linked are the bomb, for sure. But then he needs a good welder. At that point, he's much better off just getting the right parts to begin with. JMHO

-
 

xblitzkriegx

Well-Known Member
Established Member
Joined
May 24, 2010
Messages
1,410
Location
Earth
In his original post, he's using words like "fudge it together" and "cheap as possible". I totally concur, those parts like you linked are the bomb, for sure. But then he needs a good welder. At that point, he's much better off just getting the right parts to begin with. JMHO

-

An exhaust shop won't charge that much for a few welds.

I think your last sentence sums up most people's point in this thread. It doesn't have to cost a million bucks to be right, just not be some rigged up ole bullshit lol
 

Mojo88

"Hammer" Time
Established Member
Joined
Jan 30, 2017
Messages
1,319
Location
RI
An exhaust shop won't charge that much for a few welds.

I think your last sentence sums up most people's point in this thread. It doesn't have to cost a million bucks to be right, just not be some rigged up ole bullshit lol

100% agree - do it right, not some jury rigged POS job.

RE: exhaust shop welds. I did exhaust work on my Roush a few years back, I needed welding, so I measured and cut and aligned all pieces, then took the parts to local guy for some TIG welds (304 stainless). The first two welds (weld two pipes), he charged me $100. I didn't say a word, but got so irate that I bought my own TIG machine and supplies for $1,000.... then spent next two months practicing, and then finally did my own damn TIG welds, LOL. They came out better than the local pro, haha, but he wasn't being as meticulous as me, I'm sure. TIG requires microscopic precision....... you gotta be ridiculously controlled.
 

RoadZOmbie

Active Member
Established Member
Joined
Jan 3, 2004
Messages
5,366
Location
Somewhere Between Heave and Hell!
Good Afternoon!

I accidentally messed up and bought 3" headers and mid pipe for my build when I meant 2.5"

Two questions:

One, can I fudge the stock catback to merge? At this point I'm just trying to get it all back together as cheap as possible ?(long explanation coming in my future "finally finished" thread)

Two, when I have the money I wanted to go with the borla #14445 as my catback, except that is only in 2.5" so I would need to build this kit from pieces. I can buy the mufflers from borla no problem, but Flowmaster makes "universal kits" are these worth it? I could just assemble what I need and then have a shop weld it together yes?

do you have a 5.0 or 4V cobra? I ask because you mentioned the borla #14445 catback and it’s listed only for 94/95 cars. I was also interested in that catback but I was curious to know why it wouldn’t fit the 96-98 cobras as well.
 

Vigilante

Active Member
Established Member
Joined
May 17, 2007
Messages
1,159
Location
Phoenix
Sorry for the long reply!

Ok, so the brand is BBK.

I'm not complaining about 3" as my future goals are perfect for that size anyway. Basically this was a "while I'm in there purchase"

I'm connecting to stock exhaust now because after I settle some bills, my plan is to do a catback proper. So the quality of the reducers is a non issue since this is a temporary solution I have scheduled to change after tax season next year.

Which, because I love the borla kit, the plan was to order some pipes and muffler, then have a shop weld everything together for a custom not custom exhaust, if that makes sense?
 

Vigilante

Active Member
Established Member
Joined
May 17, 2007
Messages
1,159
Location
Phoenix
It's a 4.6, but the exhaust I have currently is 3"

The part number 14445 does fit our cars (and was the only borla at the time that did fit when I first researched it) but it doesn't fit my new headers and mid pipe because I can't read :/
 

Steve96cobra

New Member
Established Member
Joined
Oct 9, 2020
Messages
14
Location
California
do you have a 5.0 or 4V cobra? I ask because you mentioned the borla #14445 catback and it’s listed only for 94/95 cars. I was also interested in that catback but I was curious to know why it wouldn’t fit the 96-98 cobras as well.
In my experience they are too short, i had to bend hangers and force connection to mid pipe on my old 96, my current 96 has the proper year and fit perfectly it is a few inches longer.. (flowmaster) but im sure same as borla as far as why they have different part numbers.
 

Users who are viewing this thread



Top