Need advice. Long tube headers no cats...but want quiet.

mustangford289

Founding Member
Sep 16, 2001
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Florida
I am going to install long tube headers, delete the cats, install a new H-pipe, to the stock GT mufflers.

I want the exhaust tone to be as quiet as possible without cats.

I was wondering if you guys had any ideas as how to keep the noise down? I was considering glass packs, but I don"t think that they would last long....High flow cats is an option but they are very expensive....

Any ideas? thx
 
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Get some resonators welded in, many say that is the key to quieting a cat-less car down. I ran the stock mufflers with LTs and an O/R H for a while, fairly quite at idle and part throttle, but very loud at WOT.
Dan
 
Any recommendation on where to buy resonators or which brand?

That depends on what you want, how quiet really. Resonators are simply larger chambers that are empty, then you have bullet mufflers which is essentially a resonator with muffling material in the chamber instead of being empty, and then you have larger mufflers with more space/material to muffle the sound, and of course baffled or chambered mufflers which work using wave cancellation.

This is a good example of the first three.

Resonators with cancel some of the sound, making it a little quieter and generally get rid of some or all of the raspyness and trumpeting. Bullet mufflers will do similar but quiet the car down more. I'd say if you added M-80's to the stock mufflers you'd have a car close to stock quiet, though very different sounding.
Dan
 
I am going to install long tube headers, delete the cats, install a new H-pipe, to the stock GT mufflers.

I want the exhaust tone to be as quiet as possible without cats.

I was wondering if you guys had any ideas as how to keep the noise down? I was considering glass packs, but I don"t think that they would last long....High flow cats is an option but they are very expensive....

Any ideas? thx

What hi-flo cats were you looking at? I found some that are very inexpensive at 2.5" Thunderbolt Metallic Catalytic Converter 415250 - 415250 I'm having the Pypes mid mufler system installed on Monday. If you go the Pypes website and check out their install gallery you'll see the same cats on the yellow mustang.
 
Any recommendation on where to buy resonators or which brand?

you could get Pypes M80's, dynomax, magnaflow

Thx guys, I am going to try the long tubes, no cats and stock mufflers. If that is too loud I think I will try adding resonators/ M80's..

Stock mufflers with no cats sounds very raspy and trumpety. FWIW, I have the pypes MM system, which with the LT and no cats is REALLY loud (too loud, bad for my hearing). So I took off the muffler delete pipes and threw on the stock mufflers, the car is now VERY quiet, stock quiet, though it doesn't sound like stock more throaty and more bass.

This was just a temporary solution, proof of concept really. I wanted to make sure it would work before I went and bought a different catback. My next step, as it is too quiet now, is to replace the M-80's with some resonators to see how that sounds. If that works out I may keep it, or I may try a different catback.
Dan
 
Not clear

"Stock mufflers with no cats sounds very raspy and trumpety.

So I took off the muffler delete pipes and threw on the stock mufflers, the car is now VERY quiet, stock quiet, though it doesn't sound like stock more throaty and more bass."

Dan I'm not sure what you are saying...is the raspy and trumpety also very quiet?

I have JBA Lt's and Hpipe that will go to stock mufflers...
 
Dan I'm not sure what you are saying...is the raspy and trumpety also very quiet?

I have JBA Lt's and Hpipe that will go to stock mufflers...

I have the OBX LT and O/R H. When I first put them on I used the stock mufflers, it was relatively quiet, but not stock quiet. Quiet at idle and putting around, but once it got above about 2800 or WOT it would get raspy and trumpety and fairly loud, though no drone and not too loud.

I went to the pypes mid muffler setup to try something different. The pypes system is absurdly loud with lots of drone and somewhat trumpety, though not raspy at all. This got on my nerves so I put the stock mufflers back on, so I now have the LT's into the O/R H into the mid mufflers (pypes M-80s) into the stock mufflers (double muffled). No drone, no raspyness, no trumpeting, and about as loud as stock. The tone is different, deeper and more throaty, but about the same volume.
Dan