How to quiet down a stroked 383

[RichardGoesFast]

Dynomax super turbos are very quiet, maybe too quiet. My car has 600hp and at idle to 1500rpm the car is pretty mellow driving through the neighborhood. Screams at WOT. I also run an h pipe, I don't think that will have much of an effect on sound volume but if you don't have it and are already doing exhaust work I would add that or an X.

This is good to know. What I decided to do was install 24" Summit Racing glasspacks between the existing mufflers and tailpipe ends. Will work on those this week and see how they work. Will report back. If they don't work I'll look into the Dynomax Super Turbos, I have heard about those. Thanks!

 

[70bigblockdodge]

Put the pipes together with a H or X and problems will go away, and it will flow better as a bonus.

 

[Splangj]

Sounds like you have flowmasters? I had those on my 408 Dart. They had horrible drone, and were very loud at WOT. My RR has 3” exhaust with an H pipe and Dynomax turbo mufflers. There’s a reason TTI specs Dynomax mufflers. Great power potential and I feel a great sound with no drone. Why add resonators to correct a flawed system, it’s just adding weight, clutter and giving more areas to leak/fail?
Almost everyone around here with a modern car or truck runs Flowmasters. You can hear them coming from miles away and they’re a dime a dozen

 

[Runcharger]

Yeah: If it has Fartmasters then that's the problem.

 

[VANDAN]

I have to ask, Why do you want to quiet it down ? I drive my Mopars, to hear the sound, and watch people turn their heads, mostly smiling, as they remember those days. I never have a radio on, as that engine beat, is "Music" to my old ears...

 

[Some Car Guy]

I’m interested in putting resonators on my stock 69 GTX. I’m thinking the repops would be good. Shop recommended magnaflow can style. I have a drone I hope to quell.

 

[RichardGoesFast]

This is good to know. What I decided to do was install 24" Summit Racing glasspacks between the existing mufflers and tailpipe ends. Will work on those this week and see how they work. Will report back. If they don't work I'll look into the Dynomax Super Turbos, I have heard about those. Thanks!

Good news here, the 24" glasspacks were too long so I used 18" glasspacks with band clamps. The results are positive, the drone is almost entirely gone, and the overall volume is reduced. Sounds like about the same volume as the original 383 but maybe a little louder, hard to judge. A little louder is no problem at all, it was just way too loud before these glasspacks. I put them after the stock mufflers. Again, Colby at Accurate Exhaust was a great help in coming up with this solution. So happy!

 

[BigLime]

Sorry- Somewhat older thread.

I have HP manifolds on basically a stock 440, a 2 1/2" exhaust all the way out the back with dual Dynomax Super Turbo's (14") and I can't stand the drone.
I do not have an X or H pipe.
I do have 3.9 gears and about a 26" tire so I am getting to around 3200 RPM on the freeway. Even so, it is hard to stand just cruising at 45 or so.

I must be getting old. You guys recommend the same muffler I have to reduce drone. Is there anything else out there that is quieter?
Maybe add resonators?

Thanks in advance.

 

[SlinktRR]

I would add the x pipe? Maybe you get bad resonance with no crossover.

Hard to say definitively, this stuff is very subjective. My car is 600hp 499 with super turbos good sized solid cam and an H pipe, regularly take it up to 80+ mph on the freeway and the sound is mild. Idle is nice but the neighbors don't complain on a Sunday morning.

 

[33 IMP]

Sorry- Somewhat older thread.

I have HP manifolds on basically a stock 440, a 2 1/2" exhaust all the way out the back with dual Dynomax Super Turbo's (14") and I can't stand the drone.
I do not have an X or H pipe.
I I have to reduce drone. Is there anything else out there that is quieter?
Maybe add resonators?

Thanks in advance.

Yes. Research Helmholtz resonators. Basically a "j" pipe with a capped end that you splice in alongside of your exhaust pipe. With the right length (calculations, formula available on line) it WILL kill the drone, and nor affect performance at ALL! Done right, a win-win.

 

[hunt2elk]

Sorry- Somewhat older thread.

I have HP manifolds on basically a stock 440, a 2 1/2" exhaust all the way out the back with dual Dynomax Super Turbo's (14") and I can't stand the drone.
I do not have an X or H pipe.
I do have 3.9 gears and about a 26" tire so I am getting to around 3200 RPM on the freeway. Even so, it is hard to stand just cruising at 45 or so.

I must be getting old. You guys recommend the same muffler I have to reduce drone. Is there anything else out there that is quieter?
Maybe add resonators?

Thanks in advance.

I'm kind of surprised you are getting a drone with Super Turbo's. I have had them on 5 different cars now with no issues at all. I do have "H" head pipes on all of them however.

 

[Pool Fixer]

Sorry- Somewhat older thread.

I have HP manifolds on basically a stock 440, a 2 1/2" exhaust all the way out the back with dual Dynomax Super Turbo's (14") and I can't stand the drone.
I do not have an X or H pipe.
I do have 3.9 gears and about a 26" tire so I am getting to around 3200 RPM on the freeway. Even so, it is hard to stand just cruising at 45 or so.

I must be getting old. You guys recommend the same muffler I have to reduce drone. Is there anything else out there that is quieter?
Maybe add resonators?

Thanks in advance.

I got the bad droning 440, .474 purple shaft cam, manifolds, h pipe, 2.5” exhaust with 2 chamber flow masters.

Summits cheapest cherry bomb knockoffs used as resonators after mufflers totally got rid of it.

Droning only became a think when I switched from headers to manifolds.

I have some videos in YouTube of it running. I’m “that guy” on you tube. The whole channel is 4 clips of my charger you can’t miss it lol

 

[68 Sport Satellite]

Yes. Research Helmholtz resonators. Basically a "j" pipe with a capped end that you splice in alongside of your exhaust pipe. With the right length (calculations, formula available on line) it WILL kill the drone, and nor affect performance at ALL! Done right, a win-win.

I did this with my car and it works great. No drone. I'll try to find some photos to post. I believe the blind capped end J-pipe length is 28 inches for each side.

 

[Some Car Guy]

I'm kind of surprised you are getting a drone with Super Turbo's. I have had them on 5 different cars now with no issues at all. I do have "H" head pipes on all of them however.

Pretty sure every car I’ve had with super turbos had a drone. Running a blocked heat crossover will contribute I believe.

 

[BigLime]

Seems like what most of you have in common is the H-pipe. I think I will leave the super turbos on and try that first.
Thank you!

 

[747mopar]

If it's mostly resonance that you're hearing first go over everything and make sure nothing is touching the car and everything is nice and tight. I've had pipes get smacked to where they were gently touching the floorpan and it gets surprisingly noisy, same with missing or loose hangers. Also I've had certain tips that act like megaphones.

My current exhaust is an X pipe with average sized free flowing mufflers, don't remember the brand but they're straight through (like an S). It's still a bit loud but comfortable for me.

 

[BigLime]

If it's mostly resonance that you're hearing first go over everything and make sure nothing is touching the car and everything is nice and tight. I've had pipes get smacked to where they were gently touching the floorpan and it gets surprisingly noisy, same with missing or loose hangers. Also I've had certain tips that act like megaphones?

Thanks- I've done it once but I will go over the exhaust again.
I do have the rectangular tips that were popular in the day. Can tips make that much of a difference?

 

[747mopar]

Thanks- I've done it once but I will go over the exhaust again.
I do have the rectangular tips that were popular in the day. Can tips make that much of a difference?

I used to have side exit exhaust, eventually the tips got dinged up so I replaced them and oh my word were the new ones annoying as hell. But if they're the same ones you had that's likely not your problem.

 

[Don Frelier]

Thanks- I've done it once but I will go over the exhaust again.
I do have the rectangular tips that were popular in the day. Can tips make that much of a difference?

The tips will take away the sharpness and it really helps to get the outlet beyond the rear bumper.
But tips will likely not remove the drone at a certain speed you need a bigger muffler or resonator for that.
I like hemi mufflers personally.

 

[BigLime]

I used to have side exit exhaust, eventually the tips got dinged up so I replaced them and oh my word were the new ones annoying as hell. But if they're the same ones you had that's likely not your problem.

Thank you.
Wow- I did not know that tips can make a difference in drone.