Change STS muffler Tone?
Thread Starter
Instructor
Joined: Jul 2011
Posts: 246
Likes: 15
From: Pell City AL
Change STS muffler Tone?
After reading considerable reviews and listening to sound clips, I went with the STS mufflers in the Hooker side pipes of my '75 which has the full headers. Currently the end caps are installed because I wanted to control the level of the sound.
Unfortunately, I am disappointed with the "tinny" sound and was hoping for something deeper. Does removing or drilling holes in the end caps change the tone or just the level?
Thanks in advance,
Unfortunately, I am disappointed with the "tinny" sound and was hoping for something deeper. Does removing or drilling holes in the end caps change the tone or just the level?
Thanks in advance,
Le Mans Master
Joined: Apr 2000
Posts: 7,562
Likes: 9
From: B'Ville NY
Cruise-In III Veteran
St. Jude Donor '05
Yes, I removed the caps, but they were a bit too loud so I welded them back on. They are engine soft plugs so they can easily be replaced if you don't like what you've done. I found a 5/8" hole drill in each works well for me 
Le Mans Master
Joined: Apr 2007
Posts: 7,353
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From: Graceland in a Not Correctly Restored Stingray
They sound tinny to my ear as well, but others find them desirable. So, if worse comes to worse you can probably sell them to redeem some money towards something else. FWIW, I'm going with the MaxFlows, which are very deeply toned and apparently only bark loudly if you get on it pretty good. If interested, I'll try to find a clip of them to post up for you. My $.02
Instructor
Joined: Dec 2007
Posts: 207
Likes: 6
I have 7/8'' hole in my STS and had them mounted reversed with caps facing in the rear by mistake and did not like the sound at all on my BBC 568ci, sounded like I had a hole in my muffler. After switching them around and having the caps face foreword it sounds a lot better and real lumpy with the cam that I have just wished they sound a bit more dipper especially under harder acceleration.
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Le Mans Master
Joined: Mar 2001
Posts: 6,242
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From: Watkinsville, GA and Glen Cove, NY
I have run 3 sets of sidetubes and baffles in various configurations. I have full length baffles uncapped, cut uncapped and cut capped. The cut and uncapped were by far the loudest and deepest sound. They all sound good to my ear and I get to keep all my horsepower. However, now that I know God doesn't approve, I will have to change them.
Bill
Bill
Melting Slicks
Joined: May 2006
Posts: 2,590
Likes: 403
From: Nashville TN
St. Jude Donor '09
Same here -- 5/8" hole. Sounds great now. Can't wait to hear them when I raise my compression a point and get bigger cam.
Thread Starter
Instructor
Joined: Jul 2011
Posts: 246
Likes: 15
From: Pell City AL
Thanks for all the information. I am going to flip them around and drill the 5/8 hole. Some notes for future reference:
1. Talked to the MFG and they are only directional when the cap is installed. (as noted cap should be forward)
2. The standard mounting brackets on the Hooker side pipes point the exhaust to the side and need to be modified to point the exhaust 30 degrees down.
3. A small hole should be drilled in the bottom of the header collecter to prevent condensation and corrision to the header.
1. Talked to the MFG and they are only directional when the cap is installed. (as noted cap should be forward)
2. The standard mounting brackets on the Hooker side pipes point the exhaust to the side and need to be modified to point the exhaust 30 degrees down.
3. A small hole should be drilled in the bottom of the header collecter to prevent condensation and corrision to the header.
Le Mans Master
Joined: Oct 2007
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From: Richmond Kentucky
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PM sent to you Mr. obas..................
Burning Brakes
Joined: Feb 2001
Posts: 854
Likes: 0
Thanks for all the information. I am going to flip them around and drill the 5/8 hole. Some notes for future reference:
1. Talked to the MFG and they are only directional when the cap is installed. (as noted cap should be forward)
2. The standard mounting brackets on the Hooker side pipes point the exhaust to the side and need to be modified to point the exhaust 30 degrees down.
3. A small hole should be drilled in the bottom of the header collecter to prevent condensation and corrision to the header.
1. Talked to the MFG and they are only directional when the cap is installed. (as noted cap should be forward)
2. The standard mounting brackets on the Hooker side pipes point the exhaust to the side and need to be modified to point the exhaust 30 degrees down.
3. A small hole should be drilled in the bottom of the header collecter to prevent condensation and corrision to the header.
Happy B. 69502.............. I see Gods helper is back...............
Le Mans Master
Joined: Mar 2001
Posts: 6,242
Likes: 1,014
From: Watkinsville, GA and Glen Cove, NY
obas. I know you did call, and we talked about the direction of the baffles, BUT the drilling of the hole in the collector was not talked about. Condensation in the lower part of the " primary " tubes can be a problem over time if they are not stainless steel units. Just depends.
Happy B. 69502.............. I see Gods helper is back...............
Happy B. 69502.............. I see Gods helper is back...............
Bill
Le Mans Master
Joined: Apr 2000
Posts: 5,202
Likes: 10
From: cincinnati ohio
St. Jude Donor '09
Ah yes 
doing the Lords work trying to repress another generation of Koolaid drinkers.
And seeking out the already misguided to show them the error of there ways as so they can repent and give praise to the only true form of internal combustion percussion suppression brought forth by thy Hooker pipes....Amen
doing the Lords work trying to repress another generation of Koolaid drinkers.And seeking out the already misguided to show them the error of there ways as so they can repent and give praise to the only true form of internal combustion percussion suppression brought forth by thy Hooker pipes....Amen
Last edited by yellow 72; Oct 31, 2011 at 08:01 AM.
Burning Brakes
Joined: Feb 2001
Posts: 854
Likes: 0
Bill. Glad to hear it's OK from the head guy. I will say that after NINE years and that loss of $100.00, give or take, nothing has changed in lower Ohio............