An enterprising guy who can weld can make his own reproduction of the Borla muffler (or any other).
4" x 8" x 12" SS bodies, end caps, etc. here: http://www.coneeng.com/mufflers.html



From here: https://www.fiero.nl/forum/A...090907-2-090131.html

quote Posted by ssspeedstreet After considerable cutting I have the two ends apart. Unlike the diagram above, this is the interior layout of the Fiero Borla (The black dots on the pipes represent perforated sections): The inlet pipe going into the "T" is only 1.75" OD! The straight outlet pipes are 2.00" OD, but neck down to 1.75" OD after exiting the case. ... There's also ceramic "fiberglass" and stainless steel wool packing inside:

A picture of stock Fiero muffler cut open. Yellow circle is Inlet for reference.




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Calgary time/temp

3.4L Supercharged 87 GT Click me
Super Duty 4 Indy #163 Click me

[This message has been edited by fierosound (edited 07-03-2015).]

Cool. I've oftern thought about cutting one open and doing some sort of custom mods to achieve a specific sound. But would mostly be guessing.

For someone with welding skills, the Spintech muffler is not all that complicated. Some pipe, some baffles (created from 1/2 C section pipe) and a steel box is really all there is to it. It only slightly quieter than the Flotech 13" crossflow muffler at over twice the price.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

quote Originally posted by 2.5: I've often thought about cutting one open and doing some sort of custom mods to achieve a specific sound.

IMO, the trick would to be able to weld it back together without the muffler case "skin" vibrating at any given RPM.

<bump>

A lot of discussion on mufflers again.

quote Originally posted by fierosound: <bump> A lot of discussion on mufflers again.

The above... the cut-out of the Borla is really surprising to me. I read the other thread, and obviously I too know that bigger isn't better... but I'm surprised they made the exhaust so small at various points. I have to imagine that, while it was quality stainless, it was also cheap.

I'd love to see a video with a real comparison of muffler sounds... I have no idea what I'm going for with my 3.4 swap.

I don't want something that's rabidly loud, but I do want something that has a really nice note to it, and gets loud when I stomp on it.


I guess the easiest thing I can compare it to is my Crown Victoria. I installed the "Quiet-Flow" dual exhaust system that's basically the OER for the Grand Marquis LSE (Luxury Sport Edition).

Cruising around town... it's a nice throaty, but silent idle. Inside the car you don't really hear anything (miles of leather and tons of jute padding in every hole you can imagine, all stock). But when you stomp on it, that exhaust opens up and just screams...

[This message has been edited by 82-T/A [At Work] (edited 10-02-2024).]