Exhaust Sounds Raspy, Really Raspy. Any Suggestions?

I. Have a 1973 mustang. In it is a 1987 5.0. Aluminum heads pro comp dual plane intake. Ford racing 498 cam. hooker long tubes. Edelbrock 600 carb. Roller rockers. And purple hornies flashbacks. The exhaust is annoyingly raspy. What can I do about this. Is it tuning? Or do I need something in the exhaust or what. Please help. Would resonator tips stop it or turndowns or what. Thanks for any help.
 
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I. Have a 1973 mustang. In it is a 1987 5.0. Aluminum heads pro comp dual plane intake. Ford racing 498 cam. hooker long tubes. Edelbrock 600 carb. Roller rockers. And purple hornies glasspacks. The exhaust is annoyingly raspy. What can I do about this. Is it tuning? Or do I need something in the exhaust or what. Please help. Would resonator tips stop it or turndowns or what. Thanks for any help.
 
My first guess would be those mufflers but it could be tuning issue as well. IMO chambered mufflers give the best sound without that raspiness. Glasspacks generally let the exhaust pass strait thru without much backpressure. What diameter pipe are you running?
 
I don't think turn downs would do anything for you other than bounce your soundwaves off the pavement and yeah it'll sound different but you'll have the same issues. Resonators are basically glasspacks that may muffle a little bit more of your sound. Back in the day it was all about less restriction and making our cars loud and rumbly. The mustang I had in 1976 could be heard coming from miles away but in reality probably sounded like hell. Mufflers have come a long way since then. Its all about nice sound and performance. Now mufflers are designed with different chambering to give different levels of backpressure and are made to bounce the different soundwaves around inside those chambers. Different designs will give different results.
You might try Dynaflow website and tell them what you have and get their suggestions
 
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Raspiness is inherent with glass packs and you'll need to switch to a chambered muffler if you want a diff sound. Now you could add an h-pipe to minimize popping or have the system checked for leaks. Leaks at the headers or the welds in the system can cause popping. Turn downs just echo your exhaust sounds and usually vibrate the inside of your car to the point it's nauseating. Resonators in the exhaust tips may help; they were used in '66 GT350s to quiet the exhaust.

I run 2.5" side exhaust, h-pipe, and 18 inch Cherry bomb glass packs and it sounds great. really crisp and old school sounding but it doesn't ever drone or cause excessive noise inside.
 
Mines really raspy too I have x pipe no mufflers or cats lol it's not loud till right at 3k then it's like a vtec hits lol a ford vtec lol idk but mines really weird out of all the mustangs I've had this ones just sounds different. It could be the tune as well like someone else said.
 
I see the original posting is a little old and the original author hasn't responded since his first post date, but I can try to give a little insight since it seems to have picked up a little steam again. I am no exhaust engineer or guru, so this is my layman's guide....

Glass packs are essentially a straight through design with only a little sound deadening material. They are designed for the best possible flow while helping to quiet the engine. So, straight pipes and glass packs are essentially the same sound, including raspiness.
glasspacks-cutaway_lg.jpg


Turbo mufflers also contain a packing material similar to glass packs, but are not a straight through design. The changes in direction essentially bounce the sound waves around within the muffler and through the packing material to help control the sound it emits.
turbo-cutaway_lg.jpg


Both turbos and glass packs have perforated or louvered tubes within the muffler for the sound to travel through to quiet it. Turbos are inherently quieter due to the extra surface area of the louvered and packed tubing as well as the changes of direction within the muffler.

Chambered mufflers are designed to give a certain frequency of sound and cancel other frequencies. They are divided into "chambers" which have different diffusers in different design layouts in order to cancel frequencies and have no packing material, giving them pretty good flow. Chambered mufflers, IMO, are the only mufflers engineered to give a wanted sound while canceling unwanted sounds such as raspiness.

ST-1409-LIP-11-e1404406362373.jpg


For comparison, here are a couple vids of my Cobra II, one with turbos and one with Thrush 2 chamber mufflers. The 2 chambers sound a lot better IMO. I have to give a small disclaimer here though, when I installed the 2 chambers, I also installed an H-pipe.....

Turbo:

View: https://youtu.be/K5KE6B-hIqU


Chambered:

View: https://youtu.be/oIreFUOfLZw


Another chambered:

View: https://youtu.be/lgGduu0N3Rw


I hope this helps. Like I said, I'm no expert on exhaust systems by any stretch of the imagination.....
 
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