Looking for a muffler that will fit the Mufflex 4" system and not be too loud for the street (cops). I am willing to sacrifice a lil bit of performance but nothing too drastic.

 

I'd say check out Magnaflow's line of mufflers. They are pretty mellow sounding compared to the Flowmaster or Spin Tech those systems typical come with.

 

look into the Dynomax ultra flos. They are one of the quietest ones out there. I am looking at #17517 a 3.5 muffler

 

4" brother...not 3.5 Only Ultra Flows I have seen are the bullets which are far from quiet

btw the only mufflers i have seen in the 4" are race only.
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i was looking at the 4" magnaflows, but all of them say racing muffler, so i am thinking those dbl levels arent down to what the muffler is on my car at this moment.

 

you will be hard pressed to find a 4" muffler that is not labeled a "race muffler"
im using a dynatech splitflow race muffler and a 4" turndown with a cone baffle in it, it has a bit of sound but it quite reasonable.

 

Yeah I know I was hard pressed for this, thats why I called in for help from you guys!

That dynotech race muffler...how does it compare to the Dynomax Bullet sound wise at idle and cruising saying 2000-3500 rpms?

 

i had that on my car and it was ridiculous. Pure race car I switched to the 4 inch in/out ultraflo round 6" case (not a bullet) and it got quieter but still very loud. I mounted it in the I pipe and ran a bunch of tail pipe after it, dual exits out the bumper and it got alittle quieter but still very loud on the throttle while driving. I dont get cops on me but my local guys are pretty lenient on cars. Its a hot rod town with a lot of car shows.

I think one of the spintechs or flowmaster that the mufflex comes with is as quiet as your gonna get.... which even then aint that quiet

What i'd try to be quiet is the mufflex system using the crossflow stock style muffler they have from spintech. 4" single in, dual 3" out. Just like a flowmaster 80 series but bigger

the other option that MAY work is the Ultraflo round thats 9" round in the case, 4" in and pretty long. Mount it in the rear where the stock muffler was and it may quiet it down more than my 6" round case

 

ridiculous huh? Im actually quite surprised at how reasonable it sounds. Its not quiet by any-means, but its just a little louder than the 80 series flowmaster it replaced and sounds much better, no rasp, resonance. Maybe im just used to loud cars, or im deaf .

i dont know if the placement has anything to do with sound? it mounted up front where the cat would be. and im sure the turndown helps

 

Nothing says you can't build your own muffler & get the sound level you want.

 

Alright guys.....found two Magnaflow mufflers that says they arent "Racing" mufflers....they say they are performance mufflers, just like the one i have on my car. part numbers MPE-12770 and MPE-14594.

One is oval, one is round. I am hoping that the round one will be quiet like the typical Magnaflow "street series" as i call them, bc the oval one (although it has dual outlets) is 80 bucks more and the mufflex i am getting only has one tailpipe coming with it. Hmmmmm choices choices..

if they only made the Hooker Areochamber in the 4" inlet I'd be a happy camper.

 

never thought of that approach, wonder how that would work

 

dynomax makes a quite a few 3.5 welded mufflers that flow enough for most engines. If they are going to be to loud just put a 3.5 cat on there. You may lose 5-6 horse, but mother nature will thanks you
That first muffler number was a diesel muffler. I don't know if that makes a difference or not?

 

I was considering making my own case muffler out of sheet/plate metal. It wouldnt be that hard i dont think just need to take your time with the welds and the placement of the passage way.

i was gonna run a box type case with a exhaust tube running thru, but ported out with holes all thru it, much like a cheese grater or so. Then wrap fiberglass packing/fiber all in the case. I wanted to make the top of the muffler case removeable to allow different amounts of packing to get the sound i want, and once its correct, i'd weld it shut again. I dont think i'll need to do that with my new setup tho. I think it will quiet down nicely

I dont know. I had the car with open headers and it wasnt all that much louder than with the pipes/muffler. I did a test with all the mufflers i had, the ultraflo, and dynatech split flow. I ran them dumped before the tires with the muffler where the driveshaft bolts to the rearend. I startd the car with open headers, listened to it, then shut it off. Changed to the split flow, did the same test. Then with the ultraflo. Ultraflo was noticeably quieter but only by alittle bit compared to the split flow.

I did WOT test with both mufflers inside the car, and the splitflow gave a killer tone, just plain mean but very loud. The ultraflo sounds amazing too, slightly different tone but pretty loud. Abit quieter tho than the splitflow.

Then i finished the exhaust by running up over the axle, into dual 3" pipes outthe rear bumper. That really toned the car down abit but still very loud

I took a decible meter and measured it at idle on a cold startup while it was warming up, and i believe it was idling over 85 dB. Alittle bit of throttle and it was in the high 70's/low 80's about 50-60 ft away, and near 90 db behind the pipes. It was mean.

Heres first startup with the split flow dumped over axle. higher idle speed but you can hear its mean as hell and pretty loud
http://media.putfile.com/383-Stealth-Ram-Startup

warmer idle with better tune... about 950rpm with ultraflo and completed exhaust
http://media.putfile.com/383-HSR-Ultraflo-muffler-idle

 

it says one of the mufflers is for diesel that shouldnt matter should it?

 

i wouldnt think so. diesels just tend to be 4" or larger and mufflers for them should work for cars that need 4" or larger exhaust

 

awesome i was hoping for that

 

I was actually considering running two magnaflows, one across in the stock postion, and a "u" pipe going into another sitting right next to it. There's plenty of space, but that starts getting expensive.

I thought it was very interesting to see that when I got the 4" system out, you can see where it was rubbing on the bottom of the chassis in several places pretty good, which vibrated the snot out of the car at freeway speeds. If you trim your fuel tank bash panel in the right places and keep the tubing from vibrating the bottom of the chassis, it might be workable with the SpinTech. No matter what you do, at full honk a 4" system is not going to sneak up on anyone.

Happy Hollidays you Gearheads!

TA

 

you can find complete sets in stainless on e-bay for $300.00 for the camaro. they use the same ones that are used on the old vetts.
but before you do it, ride around for a while in a car with side exhausts with the windows down. remember you are going to be 4 feet from the open pipe and after the first 100 miles you might decide that its not the way to go. its worth the test. i did and decided that i did not want them even though they looked hot. i drove around in a side exhaust vett for 2 days.
here in california you cannot run highter than 95 db and they did not exceed that. think of being in a stones concert standing next to the speaker every time you have to drive your car and you get an idea how loud it is to you as you drive.
but they do look hot.
http://media.putfile.com/383-Stealth-Ram-Startup came from 383 stealth ram above. it sounds hot, but imagine yourself with that in YOUR EAR every second you drive. i love that sound, but i want others to hear it.
here is the link for the guy that makes the side exhausts on e-bay. http://cgi.ebay.com/ebaymotors/ws/eB...%3AIT&viewitem=

 

http://video.cardomain.com/Clip.aspx...D884C4BBA3A71B

I don't think the flowmaster is that loud. Cops around here don't notice me.