BOA279

iTrader: (1)

I failed inspection for "excessive noise" The limit is 95 DB @ 2500 RPM.... I had 102.5 DB I've been reading other forums but I can't seems to find any information about quieting down a loud mouth. I'd like to know from dynomouth and borlamouth owners what the difference sound wise is? I can't drive the car until its fixed so HELP HELP HELP!!!

Exhaust experts: What muffler would you recommend to drop 10-15 DB or more without sacrificing much performance? Should the muffler take the resonator's spot or be welded in elsewhere?

THANKS IN ADVANCE!!!!

ChocoTaco369

Well, first thing you need to understand is that every 3 dB is double, so if your exhaust was 98 dB, it would be twice as loud as the legal limit.

To make the math easier, we'll say you need to drop it 9 dB, which is half the loudness, then half of that, then half of that. So it needs to be EIGHT TIMES QUIETER. In reality, it's more like 6 or 7 times quieter to just squeeze by. Keep that in mind.

You need cats and a whole new catback in order to do that. That may not even be enough. Sounds like it's new catback + cutout time

If you only want a muffler and not a whole catback, your only options in reality are a Magnaflow muffler, a Hooker muffler or an SLP dual/dual muffler. Bullets will NOT help in this case, so don't waste your money on them.

mOtOrHeAd MiKe

iTrader: (8)

In tip exhaust silencers. A simple fix really...

odarabla

iTrader: (1)

[QUOTE=ChocoTaco369;7917535]Well, first thing you need to understand is that every 3 dB is double, so if your exhaust was 98 dB, it would be twice as loud as the legal limit.

To make the math easier, we'll say you need to drop it 9 dB, which is half the loudness, then half of that, then half of that. So it needs to be EIGHT TIMES QUIETER. In reality, it's more like 6 or 7 times quieter to just squeeze by. Keep that in mind.

You need cats and a whole new catback in order to do that. That may not even be enough. Sounds like it's new catback + cutout time

If you only want a muffler and not a whole catback, your only options in reality are a Magnaflow muffler, a Hooker muffler or an SLP dual/dual muffler. Bullets will NOT help in this case, so don't waste your money


I don't know?? I have the magnaflow exhaust on my car. It's pretty quiet at idle but now that I have the headers on and the car is catless. It's pretty damn loud when I get on it!! @ 2500 rpm the damn rearview mirrior vibrates.

Black FormulaLs1

iTrader: (10)

keep your foot out of it lmao...good luck in your search tho...i think you can go to www.ls1sounds.com and there are links to different exhaust sounds...

BOA279

iTrader: (1)

I guess I needed to post more info: Mac LS1 headers (mids) with y-pipe and 2 cats into SLP loud mouth. If that helps any

MaroMan

iTrader: (6)

Is yours welded or slip fit, i was smart and slip fit, so cheap autozone muffler + steel wool equals PewterSS's homemade quietmouth for a day

JohnnyC

Find a different inspection shop for God's sake. What did you expect from the LM1? I'm sure there are plenty of redneck mechanics out there who would think your car is cool and not care about the dB check.

blueeyeddevil141

iTrader: (5)

I was told I DB'ed 75 over the legal limit for a motorcycle when I ran open headers, I was so proud.

mvvette97

iTrader: (18)

Put a bullet in each tailpipe. that's what i did and really like it. Here is what mine sounds like.

ChocoTaco369

That'll be a waste of money. It won't lower the car's dB hardly anything at all. Right now, his car is nearly 8 times louder than the legal limit.

ErikElvis

iTrader: (1)

The cheapest solution.... Steel wool. I failed and then stuffed each tail pipe with about a foot of steel wool. I had dual dual tips so it was hard to see. If you have shotgun tips you may be able to get away with it. I bought some steel wire and slipped it over the pipe and then put the tip over the wire so the wool didnt come out.

ChocoTaco369

Haha, that's actually a pretty good idea

MaroMan

iTrader: (6)

I just installed a 29inch regular glass pack and my car now sounds like a honda instead of a mean *** LS1 with loudmouth exhaust. I will let you know tuesday if i make it through inspection.