Bracket Talk
Muffler suggestion for 509" BBC Camaro drag car with 4 Inch open collector headers?

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October 18, 2021, 08:19 PM
Rich Paton III
Muffler suggestion for 509" BBC Camaro drag car with 4 Inch open collector headers?
Thinking about running mufflers on my 69 Camaro drag car running a 509" BBC that runs 5.90's with open headers. Want to take the sting outta the rev.

Looking for recommendations based on personal experience in regards to fit, form and function.

Not into any debate as to personal preference.

Thanks in advance!
October 19, 2021, 08:30 AM
1320racer
1. Any case style muffler will kill power/mph.
2. Any muffler installed off the collectors, under the floor will rattle your teeth out from the vibration inside the cabin.
3. Bullet style mufflers do nothing to suppress noise and should only be used when a muffler is required for the class you run.
4. I run a perforated cone in my collectors, installed many years ago to meet a muffler rule for a class that I ran that did not have a db requirement. These “vortex” cones are made by Dynatech and do soften the tone of open headers, 1-3db according to Dynatech but are not a muffler and do not suppress the open header sound. They are are also available installed in a turndown and that’s what I have which also helps to disburse sound.



This message has been edited. Last edited by: 1320racer,
October 19, 2021, 11:51 AM
Rich Paton III
[QUOTE]Originally posted by 1320racer:
1. Any case style muffler will kill power/mph.
2. Any muffler installed off the collectors, under the floor will rattle your teeth out from the vibration inside the cabin.
3. Bullet style mufflers do nothing to suppress noise and should only be used when a muffler is required for the class you run.
4. I run a perforated cone in my collectors, installed many years ago to meet a muffler rule for a class that I ran that did not have a db requirement. These “vortex” cones are made by Dynatech and do soften the tone of open headers, 1-3db according to Dynatech but are not a muffler and do not suppress the open header sound. They are are also available installed in a turndown and that’s what I have which also helps to disburse sound.



Thanks Ed. I am using the cones now, but was looking to knock a few more db's off. Running a tenth slower isn't a concern as much.

Not sure what mufflers folks are using with similar applications.
October 19, 2021, 12:47 PM
pauley
I run a kooks muffler on my camaro. Bullet style about 14” long and put some turn out on the end of them. Told them what my collector od was and they made me some to slide over collector. Also installed collector tethers to meet requirements. They sound good with my small block. Don’t know if any et difference as I have not run without them. They fit good to the under side of car and do not vibrate anything. Kooks are stainless as well. They will probably put the turn outs on them for you.

ep

I gonna say very little et loss if any
October 19, 2021, 01:24 PM
HS professor


Problem is a 3.5" or 4" muffler is usually pretty big.We have these giant 3.5" flowmasters on the truck. Things are big and heavy but quiet is down real nice. We have a small bullet style on the Firebird, forget the brand but it's still loud as hell.
October 20, 2021, 01:15 PM
Rich Paton III
quote:
Originally posted by HS professor:


Problem is a 3.5" or 4" muffler is usually pretty big.We have these giant 3.5" flowmasters on the truck. Things are big and heavy but quiet is down real nice. We have a small bullet style on the Firebird, forget the brand but it's still loud as hell.


Do you know the diameter of your mufflers on the truck?
October 20, 2021, 01:32 PM
Curly1
I run the large bullet style mufflers on my 67 Camaro and they worked great. I also have turnouts to direct noise and fumes away and it helps a little.

Much quieter than open headers and I do not think they hurt ET or MPH at all. And they do not rattle, I have them with a rubber muffler hanger to help support them in the back so there is no metal to metal or vibration.


https://postimg.cc/gallery/np3zpruo/
"Dunning-Kruger Effect"
-a type of Cognitive bias where people with little expertise or ability assume they have superior expertise or ability. This overestimation occurs as a result of the fact that they do not have enough knowledge to know they don't have enough knowledge.

Before you argue with someone ask yourself, "Is this person mentally mature enough to grasp the concept of a different perspective?" If not there is no point to argue.

4X NE2 CHAMPION. 2020 TDRA NE2 Champion
October 20, 2021, 01:42 PM
Curly1
If you want really quiet it is going to cost you some weight, ET and money. But the bullet style (Dynomax?) mufflers on mine work great.


https://postimg.cc/gallery/np3zpruo/
"Dunning-Kruger Effect"
-a type of Cognitive bias where people with little expertise or ability assume they have superior expertise or ability. This overestimation occurs as a result of the fact that they do not have enough knowledge to know they don't have enough knowledge.

Before you argue with someone ask yourself, "Is this person mentally mature enough to grasp the concept of a different perspective?" If not there is no point to argue.

4X NE2 CHAMPION. 2020 TDRA NE2 Champion
October 20, 2021, 05:24 PM
TheBlueTruck
This is the Exhaust on my old truck. I like the noise behind me. The first few passes next year there will be a rust cloud. Do Ya'll think the cones would be a good replacement for the 5" mufflers?




Regan Wilson Super Street 469C
October 20, 2021, 05:42 PM
TheBlueTruck
Ed? I'm looking for advise.


Regan Wilson Super Street 469C
October 20, 2021, 06:07 PM
1320racer
all the cones do is soften the raspy tone, they are not mufflers and do not suppress sound. That said, you will run quicker/faster due to the loss of weight and opening up the exhaust
October 20, 2021, 06:29 PM
TheBlueTruck
Thank's Ed


Regan Wilson Super Street 469C
October 21, 2021, 05:41 AM
Rich Paton III
quote:
Originally posted by TheBlueTruck:
This is the Exhaust on my old truck. I like the noise behind me. The first few passes next year there will be a rust cloud. Do Ya'll think the cones would be a good replacement for the 5" mufflers?



I currently have the cones installed, and they don't really decrease any dB level. Not worth it.
October 24, 2021, 11:06 PM
Nova Go
Using Borla XR1 4” for 16yrs. Makes 565bbc 900hp sound livable. Exits at rear axle 5.5ft behind collectors.
No e.t. differences when removed half way through a race when hangers broke. I hated how much louder the car was after removal as well. Good luck with with whatever you decide.
October 26, 2021, 10:39 PM
Goob
https://www.schoenfeldheaders.com/mufflers.html


"Despite the high cost of living, it remains popular."
Dave Cook
N375
October 28, 2021, 05:57 PM
AlkyIROC
I run two Magnaflow race mufflers under the rockers on my 588. 4" in and out and you can look straight through them so no restrictions. I went with the larger of the 2 options. With two 4" elbows to bring them out from under the car and a turnout coming off the back of the muffler so that it doesn't exit directly at the tires, the entire system adds 45 pounds to the car.

Might slow me down slightly but as a bracket racer, I just change the number on the windows. Nice thing about the mufflers is that I can hear the engine, hear tire spin etc and my ears are not ringing at the end of a weekend. If I run the car without an exhaust, I need to wear ear plugs even to just take it out of the garage.

I've had people compliment me one how nice my car sounds going down the track with mufflers.


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Best ET: 9.029
Best MPH: 150.45