Muffler suggestions.

[keith4909]

1967 GTO
I’m running 474ci with mild roller and mild build. Right now I’m running 3” with 40 series flow masters. They exit just before rear tire on each side. As of now the exhaust is just too loud and sloppy. I can’t hear my stereo. I’d like something that is a little more kid friendly but gets raspy when in higher rpms. I will likely route the exhaust to exit in the back.

[Gmachine1911]

I run the Borla Pro XS mufflers in 3” with an X-pipe and over the axle tailpipes and love the sound. Mellow at cruising and they have a good sound when you step in it. I had Flowmasters before with turn-downs that I could remove and bolt tailpipes on and just running the tailpipes made a huge difference so adding tailpipes might be a possibility as well if you’re just wanting to tone it down a bit.

[OLDFLM]

https://pontiacstreetperformance.com/psp/exhaust.html

I'm running the stainless 16" Dynomax Super Turbos on my 440cid Pontiac with a 248/260 SR and they really quieted it down with 2.5" pipes and an X-pipe vs the 3" straight through mufflers I had before with 3" pipe / H-pipe / 3" tails.

While the 3" with the straight through style 14" case mufflers (Magnaflow) sounded cool when idling into a parking lot they were just too loud for cruising and actually enjoying the car. I went with what I felt would be the quietest solution while losing the least amount of performance based on the article above. I love the end result! Muscle car lope/rumble at idle... enjoyable when cruising with the windows down... I can hear the stereo now... and it makes glorious noises when I mash the pedal!

If you read the above article you could keep your 3" in front of the mufflers and 2.5" tailpipes without affecting performance. My vote would be between the biggest Dynomax muffler you can fit or the Borla ProXS mentioned above. Both with an X-pipe. HTH

[ULTM8Z]

Another vote for Dynomax here.

[Sinnister69]

The dynomax race bullets sound really good too. Very deep rumble no rasp when you get on it

[showdog75]

Borla ProXS

[keith4909]

Do you have a sound clip?

- - - Updated - - -


https://pontiacstreetperformance.com/psp/exhaust.html

I'm running the stainless 16" Dynomax Super Turbos on my 440cid Pontiac with a 248/260 SR and they really quieted it down with 2.5" pipes and an X-pipe vs the 3" straight through mufflers I had before with 3" pipe / H-pipe / 3" tails.

While the 3" with the straight through style 14" case mufflers (Magnaflow) sounded cool when idling into a parking lot they were just too loud for cruising and actually enjoying the car. I went with what I felt would be the quietest solution while losing the least amount of performance based on the article above. I love the end result! Muscle car lope/rumble at idle... enjoyable when cruising with the windows down... I can hear the stereo now... and it makes glorious noises when I mash the pedal!

If you read the above article you could keep your 3" in front of the mufflers and 2.5" tailpipes without affecting performance. My vote would be between the biggest Dynomax muffler you can fit or the Borla ProXS mentioned above. Both with an X-pipe. HTH


Any sound clips?

[Gmachine1911]

Here’s a clip of my car on the dyno with the 3” Borla’s...

https://youtu.be/CUpwuXv3b8s

[77thor]

As you know exhaust sound is highly subjective.... but...

FWIW: My 69 Camaro had Flowmasters when I bought it and I didn't like them at all.
I swapped them out for Dynomax Super Turbos and now I think it is too quiet.

[andrewb70]

I have the Borla ProXS on my Cougar and I like them a lot. If you want it quieter and you have the room, get the 19" case muffler (which is what I have).

Andrew

[BK2LIFE]

borla, magnaflow, dynomax

[keith4909]

As you know exhaust sound is highly subjective.... but...

FWIW: My 69 Camaro had Flowmasters when I bought it and I didn't like them at all.
I swapped them out for Dynomax Super Turbos and now I think it is too quiet.


I couldn’t agree more. I’d like something in the middle. Right now at idle in my garage its 95 decibels. Kids are scared of it.

- - - Updated - - -


Here’s a clip of my car on the dyno with the 3” Borla’s...

https://youtu.be/CUpwuXv3b8s


damn that sounds good and looks even better!!

[BK2LIFE]

borla, 5.3 truck 'LS'

https://youtu.be/vSGRAL3Y_3E
https://youtu.be/BlhidfjxTK0
https://youtu.be/c8QgKVh6raA
https://youtu.be/iS37jDWcTi8