Quieter Mufflers for Supercharged 5.0

[oz]

Greetings,
I have a '91 GT with a blown (Paxton/Novi 1220 SL) w/ a lot of go fast parts, including equal length Mac shorty headers, A MAC off-road H pipe, MAC mufflers and tail pipes... It's rev limited to 5100 and makes 488 hp there (stock bottom end so rev limited to keep it from 'expiring').
The problem is that when I get on it the sound it makes is just not acceptable. The volume is way too high and the actual sound is offensive. It's kind of a cracking sound... not a nice roar if you will...
Anyway, I plan to cut out the MAC mufflers and replace them - but I don't know what to replace them with... I don't want to restrict flow, but need to reduce the volume and, hopefully, make the sound a little nicer...
SUGGESTIONS?

Thanks!

 

[Noobz347]

It's rev limited to 5100 and makes 488 hp there

This [must] be a typo? Even the stock EEC runs to 6250



View: https://youtu.be/IPZ31WQjwfc?feature=shared&t=14

 

[oz]

Yea, set up aftermarket ignition with a lower RPM limit... I just checked and I shut it down at 5500....
Since the stock bottom end is 'only good for 400 hp' per most people, I figured I'd try to keep it together by limiting the revs (and therefore the boost & HP)... if the day comes I blow it up, I'll do it up right with a stout aftermarket shortblock and set the beast loose.

 

[General karthief]

2 1/2" pipes?

 

[LILCBRA]

Audio/video of the current sound you're talking about? And what exactly are you looking for - like almost stock quiet or "loud" without being obnoxious?

Assuming everything else is in good order, I'd try a pair of Flowmaster 50s. Kind of an apples to oranges comparison but I have a single in/dual out on my Ram and think it sounds great.


View: https://youtu.be/FAZs9S0FKE8

 

[oz]

I'll have to work on getting a video. Thanks for the suggestion (Flowmaster 50). I have Flowmasters on my other car and the sound is perfect - but it's not supercharged either...

I think it's 2-1/2" outlets... Not 3' I'm sure.

 

[limp]

I just went through this and from what I can find Walker quiet flow mufflers are about the quietest I could find.... All of these aftermarket mufflers are NOISY RUDE sounding to this " old " man......
Are you running any cats or other types of glass packs in your car?

 

[oz]

I just went through this and from what I can find Walker quiet flow mufflers are about the quietest I could find.... All of these aftermarket mufflers are NOISY RUDE sounding to this " old " man......
Are you running any cats or other types of glass packs in your car?

No cats... off-road H-pipe behind equal length shorties.

 

[limp]

No cats... off-road H-pipe behind equal length shorties.

You might need to do some resonators inline too... Depends on what your version of quieter is....
Problem with trying to quiet a Fox body exhaust systems is there is no room for a very large muffler at least in MY opinion...

 

[Noobz347]

Converters would go a long way to quieting things down too.

 

[oz]

Converters would go a long way to quieting things down too.

Probably true. Before I supercharged it, the sound level was what I wanted. Just some go fast parts, NA... I wouldn't want to put the stock cats back and doing it right with aftermarket cats may get pricy...

 

[Noobz347]

MRT Engineering 1979-93 Mustang V8 MRT MaxFlow H-Pipe: HiFlow Cats - 93D000

MRT Engineering 1979-93 Mustang V8 MRT MaxFlow H-Pipe: HiFlow Cats - 93D000 The Mustang V8 MRT MaxFlow H-Pipe: HiFlow Cats has a loud, deep muscle car sound and is handcrafted in T304 Stainless Steel. This system includes 2.5" mandrel bent tube with T304

www.lethalperformance.com

 

[oz]

MRT Engineering 1979-93 Mustang V8 MRT MaxFlow H-Pipe: HiFlow Cats - 93D000

MRT Engineering 1979-93 Mustang V8 MRT MaxFlow H-Pipe: HiFlow Cats - 93D000 The Mustang V8 MRT MaxFlow H-Pipe: HiFlow Cats has a loud, deep muscle car sound and is handcrafted in T304 Stainless Steel. This system includes 2.5" mandrel bent tube with T304

www.lethalperformance.com

Maybe I'll take the car over the MRT as they are about 3 miles from my home.

 

[Noobz347]

Just roll up in there and say, "It's just too darn loud."

 

[AeroCoupe]

You can just get (2) Walker 15053 universal cats for about $200 and have them installed in your existing H-pipe. That is what I did on one of my BBK x-pipes to pass inspection in Texas. Exhaust was 1-5/8" equal length shorties, 2-1/2" x-pipe, 2-1/2" cat back with Flowmaster 42's. It was pretty loud without the cats and they did quiet it up a bit.

Amazon.com

 

[rednotch]

Hooker aero chambers if you want mild / quiet. but with what holleys been doing won't be long before they get discontinued. Alot of mufflers now are all the same China made stuff with different branding since flowmaster and other brand patent expired. Never heard any call Macs crackling though, chambers are probably rotted out if there not the stainless version.

 

[Mustang5L5]

I ditched my Flowmaster 2-chambes for a set of Borla Pro XS mufflers in an attempt to quiet it down. For the most part it is quieter at idle but get loud when i step on the go pedal.


View: https://www.youtube.com/watch?v=2URLsKKwHAk