Flowmaster FlowFX mufflers

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Now I've pretty much decided that I'm NOT buying another carb, re my previous thread, I've decided the car is much more in need of a new exhaust system. I finally have had enough of the Flowmaster 40 drone, time for it to be gone!!

I'm hearing good things about the new Flowmaster FlowFX straight through on other types of vehicles, but I'm wondering if anybody has installed a pair on a Mustang 351C 4V with stock manifolds? No, I do not want to go to headers!! 

I may go to 2.5" pipes, which will be custom made, a) for cost and dollar exchange benefits and b) to support our local custom exhaust shop. If I go 2.5", I may need to open the outlets on the manifolds to 2.25" as is the Boss stock manifold, or I may just stick with the 2.25" that the car came with and save myself some work.

So guys, anyone have an honest opinion? Lots has been discussed over the last couple of years about mufflers and drone, but by all accounts these new FX mufflers do not produce any drone, which is the main goal...……. but with a nice sound.

Geoff.

 
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Thanks Kevin, why I didn't remember that post I'm not sure. Put it down to approaching old age!

Re-reading the relevant parts of the thread, I pretty much answer my own question.

There is one question I have that you can probably answer and that is; FlowFX mufflers do not have mounting hardware. Are there any problems welding the correct hangers on and where did your exhaust guy get them. Did he make them or remove from old mufflers? The 40's have the correct brackets, so I'm thinking of having them cut off and welded onto the new SS mufflers. I would also be concerned about the heat damaging the fiberglass packing. Any thoughts?

Geoff.

 
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We use to produce exhaust system components for Zeuna Starka that went on BMW and Mercedes. The cones for the ends of the catalytic converter had 3-M ceramic in the and no fiberglass. There was no filler in any of the mufflers just baffles. I would hope that current mfg. has moved away from fiberglass as a muffler component. Their muffler wraps were made from two layers of SS and very specific to the vehicle. Internal baffles would have different hole configurations and sizes. 

Mufflers are taken very lightly and really cannot be one that fits and performs for all. A simple change in rpm, cam, header length, automatic, manual makes a difference. 

Our cars came from factory with very specific exhaust systems. The 351 C 4-V came with different exhaust on the automatic than the 4 speed. 

The drone can show up in about any system and would probably be best cured with a resonator. A true performance exhaust will never be a quiet exhaust you cannot have both. You drop a little performance to gain some quiet. 

You could actually make up a bolt together resonator that you could play with different baffles inside If you wanted to learn and tune to your car. There is just not much room under there, springs, gas tank, frame everything gets in the way. 

About any system you choose will be a guess. I just wear ear plugs, lol.

 
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We use to produce exhaust system components for Zeuna Starka that went on BMW and Mercedes. The cones for the ends of the catalytic converter had 3-M ceramic in the and no fiberglass. There was no filler in any of the mufflers just baffles. I would hope that current mfg. has moved away from fiberglass as a muffler component. Their muffler wraps were made from two layers of SS and very specific to the vehicle. Internal baffles would have different hole configurations and sizes. 

Mufflers are taken very lightly and really cannot be one that fits and performs for all. A simple change in rpm, cam, header length, automatic, manual makes a difference. 

Our cars came from factory with very specific exhaust systems. The 351 C 4-V came with different exhaust on the automatic than the 4 speed. 

The drone can show up in about any system and would probably be best cured with a resonator. A true performance exhaust will never be a quiet exhaust you cannot have both. You drop a little performance to gain some quiet. 

You could actually make up a bolt together resonator that you could play with different baffles inside If you wanted to learn and tune to your car. There is just not much room under there, springs, gas tank, frame everything gets in the way. 

About any system you choose will be a guess. I just wear ear plugs, lol.
 Good info as per usual David. This has all been hashed out many times over the last while. As mentioned, I don't want quite, I want little or no drone. Flowmaster seem to have fixed that with this muffler. They're not expensive and I figure worth a shot. I'll have the system made so the can be removed and changed if necessary.

As for resonators, I worked extensively on air induction resonators, so I have a pretty good feel for that tech. 

As for ear plugs, I think more like noise cancelling head phones!!

Geoff.

 
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Geoff, I am running a muffler called Sonic Turbo. I really think you would like them, pretty much no drone. I have run them with both stock manifolds and headers, with not a big difference going to the headers. I was actually surprised that they weren’t much louder with the headers and my new engine build. Only when I really get one it are they pleasantly louder, which they should be! But I gotta tell you that when I’m just cruising around or going down the highway, they just have a really nice sound that is no way near being obnoxious. If you want to wait till next month when we meet up at the Dream Cruise or at the Ford show, I’ll take you for a ride to hear for yourself. I’ll even get send you a video with sound if you want, but I don’t think that would give you the same result as hearing it in person.

Anyway, I really like the sound and that’s it is not too damn loud either. Even the guys that rebuilt my car and engine wanted to know what they were. They said they would recommend these to everyone instead of the Flowmasters. If there’s anything that I can help you out with, just let me know.

 
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Geoff, I am running a muffler called Sonic Turbo. I really think you would like them, pretty much no drone. I have run them with both stock manifolds and headers, with not a big difference going to the headers. I was actually surprised that they weren’t much louder with the headers and my new engine build. Only when I really get one it are they pleasantly louder, which they should be! But I gotta tell you that when I’m just cruising around or going down the highway, they just have a really nice sound that is no way near being obnoxious. If you want to wait till next month when we meet up at the Dream Cruise or at the Ford show, I’ll take you for a ride to hear for yourself. I’ll even get send you a video with sound if you want, but I don’t think that would give you the same result as hearing it in person.

Anyway, I really like the sound and that’s it is not too damn loud either. Even the guys that rebuilt my car and engine wanted to know what they were. They said they would recommend these to everyone instead of the Flowmasters. If there’s anything that I can help you out with, just let me know.
 John, I'll have to check those out. If they do the job, nice sound, no drone, I'm interested. I may just go ahead and get a pair before Dearborn, but then I've been putting off doing the exhaust for the last 10 years!! A few more weeks won't make much difference.

As for the Dearborn show, I registered in the "judged class" Mach 1 Mustangs are a theme vehicle this year if you were not aware. They will be grouped together so I'm told. Judged only means appearance and cleanliness, NO MCA rules!! 

See you there,

Geoff.

 
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Geoff, I am running a muffler called Sonic Turbo. I really think you would like them, pretty much no drone. I have run them with both stock manifolds and headers, with not a big difference going to the headers. I was actually surprised that they weren’t much louder with the headers and my new engine build. Only when I really get one it are they pleasantly louder, which they should be! But I gotta tell you that when I’m just cruising around or going down the highway, they just have a really nice sound that is no way near being obnoxious. If you want to wait till next month when we meet up at the Dream Cruise or at the Ford show, I’ll take you for a ride to hear for yourself. I’ll even get send you a video with sound if you want, but I don’t think that would give you the same result as hearing it in person.

Anyway, I really like the sound and that’s it is not too damn loud either. Even the guys that rebuilt my car and engine wanted to know what they were. They said they would recommend these to everyone instead of the Flowmasters. If there’s anything that I can help you out with, just let me know.
 John, I'll have to check those out. If they do the job, nice sound, no drone, I'm interested. I may just go ahead and get a pair before Dearborn, but then I've been putting off doing the exhaust for the last 10 years!! A few more weeks won't make much difference.

As for the Dearborn show, I registered in the "judged class" Mach 1 Mustangs are a theme vehicle this year if you were not aware. They will be grouped together so I'm told. Judged only means appearance and cleanliness, NO MCA rules!! 

See you there,

Geoff.
Thanks for the info and I am planning on doing the same. I don’t think I will pre-register though. I did that one year and ended up not being able to go. I am definitely going as long as the weather permits.

 
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As for the Dearborn show, I registered in the "judged class" Mach 1 Mustangs are a theme vehicle this year if you were not aware. They will be grouped together so I'm told. Judged only means appearance and cleanliness, NO MCA rules!! 

See you there,

Geoff.
Thanks for the info and I am planning on doing the same. I don’t think I will pre-register though. I did that one year and ended up not being able to go. I am definitely going as long as the weather permits.
 I do not usually pre-register either for the same reason and I do not go to shows with any expectations of winning "something", but I got several "you aught to have entered in the judged class" last year, I though what the heck, do it!

See you there weather permitting and look forward to meeting you and hopefully some others.

Geoff.

 
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Geoff, I am running a muffler called Sonic Turbo. I really think you would like them, pretty much no drone. I have run them with both stock manifolds and headers, with not a big difference going to the headers. I was actually surprised that they weren’t much louder with the headers and my new engine build. Only when I really get one it are they pleasantly louder, which they should be! But I gotta tell you that when I’m just cruising around or going down the highway, they just have a really nice sound that is no way near being obnoxious. If you want to wait till next month when we meet up at the Dream Cruise or at the Ford show, I’ll take you for a ride to hear for yourself. I’ll even get send you a video with sound if you want, but I don’t think that would give you the same result as hearing it in person.

Anyway, I really like the sound and that’s it is not too damn loud either. Even the guys that rebuilt my car and engine wanted to know what they were. They said they would recommend these to everyone instead of the Flowmasters. If there’s anything that I can help you out with, just let me know.
 John, I'll have to check those out. If they do the job, nice sound, no drone, I'm interested. I may just go ahead and get a pair before Dearborn, but then I've been putting off doing the exhaust for the last 10 years!! A few more weeks won't make much difference.
   From what I was able to find out on the Sonic Turbo mufflers, they are old school 80's style mufflers. On a forum I found, one guy thought they were bought out by Dynomax and are now Dynomax Turbo or maybe Super Turbo.

So, how long have you had yours and where did you get them? I could not find an active listing for them for sale.

Geoff.

 
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 John, I'll have to check those out. If they do the job, nice sound, no drone, I'm interested. I may just go ahead and get a pair before Dearborn, but then I've been putting off doing the exhaust for the last 10 years!! A few more weeks won't make much difference.
   From what I was able to find out on the Sonic Turbo mufflers, they are old school 80's style mufflers. On a forum I found, one guy thought they were bought out by Dynomax and are now Dynomax Turbo or maybe Super Turbo.

So, how long have you had yours and where did you get them? I could not find an active listing for them for sale.

Geoff.

Summit it sells a fully welded “turbo” muffler.  Under $40.  Might be worth a look.

 
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   From what I was able to find out on the Sonic Turbo mufflers, they are old school 80's style mufflers. On a forum I found, one guy thought they were bought out by Dynomax and are now Dynomax Turbo or maybe Super Turbo.

So, how long have you had yours and where did you get them? I could not find an active listing for them for sale.

Geoff.

Summit it sells a fully welded “turbo” muffler.  Under $40.  Might be worth a look.
 Heard about those, I'll check them out, thanks.

Geoff.

 
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 John, I'll have to check those out. If they do the job, nice sound, no drone, I'm interested. I may just go ahead and get a pair before Dearborn, but then I've been putting off doing the exhaust for the last 10 years!! A few more weeks won't make much difference.
   From what I was able to find out on the Sonic Turbo mufflers, they are old school 80's style mufflers. On a forum I found, one guy thought they were bought out by Dynomax and are now Dynomax Turbo or maybe Super Turbo.

So, how long have you had yours and where did you get them? I could not find an active listing for them for sale.

Geoff.
I really don’t know where they came from, they were on my car when I bought it. I know the PO got a lot of stuff from NPD when he rebuilt my car, and that was in about 2010. The only thing that they say on them is Turbo. I can go take another look and get a pic of them if you want.

 

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Sonic Turbos are long discontinued, used to be made by Cyclone Exhaust. I have them on the system on my '71, found them NIB at a yard sale. They sound good, but I wouldn't go on a quest to locate them.

I usually recommend two mufflers, the Dynomax Super Turbo and the Hooker AeroChamber. Both have a nice smooth sound that is much more pleasing than the Flowmaster "rap".

 
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   From what I was able to find out on the Sonic Turbo mufflers, they are old school 80's style mufflers. On a forum I found, one guy thought they were bought out by Dynomax and are now Dynomax Turbo or maybe Super Turbo.

So, how long have you had yours and where did you get them? I could not find an active listing for them for sale.

Geoff.
I really don’t know where they came from, they were on my car when I bought it. I know the PO got a lot of stuff from NPD when he rebuilt my car, and that was in about 2010. The only thing that they say on them is Turbo. I can go take another look and get a pic of them if you want.
 John, thanks, but not necessary. Thy are probably the same as Summit sells if they just have "Turbo" on them.

I'm now leaning more towards what the custom muffler shop owner recommended and that was the Dynomaax super turbo. More money, but that isn't everything.

Geoff.

 
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