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Old 04-15-2009, 03:00 AM   #1
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Default How loud will this be?

Hey guys, I need to re do my exhaust. RIght now its just a 2.5 inch downpipe with a cat, and thats it.

What im going to do is a 2.5 inch downpipe that merges into a 3 inch exhaust.
This new system wont have a cat or muffler (money reasons). So my question is will the new exhaust be louder or quieter than the open downpipe with cat? Also, will the exhaust without muffler be loud enough for cops to care?
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Old 04-15-2009, 03:14 AM   #2
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prolly depends on where you live and how many eople complain i live in alabama and drove a mustang gt with straight pipes... (No Mufflers or cats) and i never had any problems..



IMO it shouldn't be to loud

ill be running straight down pipe when i finish my turbo install untill i can get it to a shop
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Old 04-15-2009, 03:24 AM   #3
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i have a 2.5 downpipe that merges into a 3" piping. its dual with only a resonator and its fucken loud but not annoying loud like ricer exhausts. i also have a cat though. and a test pipe sitting in the garage waiting to go on
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Old 04-15-2009, 03:51 AM   #4
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******* loud. If you don't DD the car it might be doable, but it's seriously loud. Like, "**** i'm going to get pulled over" loud.
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Old 04-15-2009, 04:01 AM   #5
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I have a full 2.5" turboback system on my car with no cat or muffling whatsoever. It is now louder with the mufflerless exhaust than it was with just an open downpipe.
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Old 04-15-2009, 04:13 AM   #6
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Quote:
Originally Posted by Fireindc View Post
I have a full 2.5" turboback system on my car with no cat or muffling whatsoever. It is now louder with the mufflerless exhaust than it was with just an open downpipe.
Thanks thats exactly what I needed. I guess ill start saving up for one of those magnaflow mufflers, I dont mind the noise but I dont want a ticket lol.
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Old 04-15-2009, 11:18 AM   #7
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performancepeddler.com
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Old 04-15-2009, 12:07 PM   #8
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I can't speak for a miata, but on a 1.8t A4 I know that a 2.5" straight exhaust with just a cat and no muffler was liveable for about a year. It wasn't really loud until you were at WOT.
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Old 04-15-2009, 12:30 PM   #9
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more like "**** I'm too loud to run at the track" loud.
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Old 04-15-2009, 12:54 PM   #10
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Quote:
Originally Posted by hustler View Post
more like "**** I'm too loud to run at the track" loud.
You guys think just one of these would quiet it down enough so as not to attract too much attention?

eBay Motors: MagnaFlow Muffler 5" Round 14" Body 3" C/C 12867 (item 270371860778 end time Apr-16-09 10:52:31 PDT)
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Old 04-15-2009, 01:07 PM   #11
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I have the Magnaflow race series muffler on my Miata and it is great. No louder than my RB system I had when I was NA (but I also have a cat). I think I paid $120 installed at the muffler shop.

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Old 04-15-2009, 01:40 PM   #12
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I'm in a similar boat. I'm really wanting to do something cheap for exhaust.

Would just that muffler really quiet the exhaust down enough? I'm thinking i'd like to do a high flow cat with that muffler and 3" piping. I think i'm a little more concerned with being quiet than you.
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Old 04-15-2009, 01:44 PM   #13
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Quote:
Originally Posted by wayne_curr View Post
I'm in a similar boat. I'm really wanting to do something cheap for exhaust.

Would just that muffler really quiet the exhaust down enough? I'm thinking i'd like to do a high flow cat with that muffler and 3" piping. I think i'm a little more concerned with being quiet than you.
addressing the cheap thing, im getting all the tube from Columbia River Mandrel Bending - Columbia River Mandrel Bending, should cost about $100 plus $90 for the muffler. If I use the welder at my old high schools auto lab It should cost me under 200.
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Old 04-15-2009, 01:45 PM   #14
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it will be ******* loud, i have vids, one sec, let me upload them, same setup ur talking about


it will get you pulled over, and it sounds like ****
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Old 04-15-2009, 01:48 PM   #15
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this last one is idle and revs, with and without muffler, no cat

get a ******* muffler, its 60 dollars on ebay

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Old 04-15-2009, 01:54 PM   #16
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lol at the muffler! Thats an awesome comparison...glad you did that.

My budget is also 200 or less. What are you doing for flanges?
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Old 04-15-2009, 01:56 PM   #17
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i brought my whole car to a local mom and pops muffler place, with a muffler that i bought on ebay for 60,

paid the guy 270, he made me a 3 inch line from the downpipe back
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Old 04-15-2009, 02:12 PM   #18
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Quote:
Originally Posted by wayne_curr View Post
lol at the muffler! Thats an awesome comparison...glad you did that.

My budget is also 200 or less. What are you doing for flanges?
I am makeing a new downpipe in that budget too. I think ill just split it after the downpipe and at the diff, and just use good old 2 bolt flanges to mate them together. Thanks urgay! Ill go with that magnaflow I linked alittle bit ago.
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Old 04-15-2009, 02:24 PM   #19
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Quote:
Originally Posted by cardriverx View Post
I am makeing a new downpipe in that budget too. I think ill just split it after the downpipe and at the diff, and just use good old 2 bolt flanges to mate them together. Thanks urgay! Ill go with that magnaflow I linked alittle bit ago.
Awesome mine will be slightly less then since I alrdy have a downpipe. I'm playing with the idea of Vband flanges but they seem so expensive...not sure if they're worth it.
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