Jaspirr

iTrader: (6)

Right now I have the Loudmouth exhaust with the resonator. Also have headers, cam, catted y-pipe, and such. I took it through inspection and it registered 106.5 decibels at 2000 RPM. The limit is 95 decibels.

I was working with one of my friend's exhaust shops and trying to figure out how to fix it. There's a bunch of different new exhaust setups I can go with, but they're all 200-400 dollars. These are such as, putting a muffler after the resonator, in the position where the stock muffler goes, but it would interefere with the whole loudmouth setup and have to be re-done. They also recommended definitely not sticking anything such as steel wool up the exhaust.

I did reading and decided that the Dynomax muffler from Summit Racing is the way to go. I want to be sure this will definitely be enough to pass inspection though. Can anybody help me with this? I know it's hard to distinguish 106db from 95db, but the last thing I want is to spend ~100 dollars on this new exhaust setup and go through inspection and have it read something like..98 decibels.

Any help would be appreciated. Thanks.

Grimes

iTrader: (3)

I have the dynomouth, and at 2000 rpm it is still pretty loud. Not sure what dB it is however - but it is less than my friends' loudmouth definitely. You could try putting on smaller tips than what came with the lm as well.

Jaspirr

iTrader: (6)

Smaller tips? I have some 2.5" single flowmaster ones that were on the car when I bought it...hmm. I don't want to cut my loudmouth tips off though.

Redneck Z

iTrader: (3)

A bullet muffler won't hardly do anything. Probably the easiest thing to do would be to buy a car chemistry insert from summit, and put it in your I pipe temporarily for the test. That would be alot easier than having to weld in a muffler, and would be easy to take out when you're done with the test.

NOBR8KSS

iTrader: (12)

Just for reference, a 10 dB drop would make the exhaust about 1/2 as loud as it is now. In other words, 100 dB sounds about twice as loud as 90 dB. I think the only muffler that has a chance of getting that quiet is the SLP D/D considering that you have headers and cam.
I have heard that the Borla XR-1 mufflers are pretty quiet for a small muffler.

Jaspirr

iTrader: (6)

I looked one up on Summit, they look nice. How would I get it into my I-pipe? Do I have to cut and weld there?

ArcticZ28

iTrader: (14)

Tell em not to take it to 2000rpm then

sidewayz28

iTrader: (24)

yeah find a hook up

Jaspirr

iTrader: (6)

All the hook up's I had turned out not working, they all got fired or quit or stopped doing it.

I ordered the bullet muffler from Summit. I don't know how this thing was supposed to help, it is a $37 straight pipe with seemingly nothing to reduce sound. I took it to my exhaust shop and they just laughed. I am thinking about ordering that car chemistry insert, but do not know how I would put it in the i-pipe. Does it have to be cut and welded?

To top it off, on the way back from the exhaust shop, after I found out I couldn't pass inspection today because of the exhaust, I got another random SES code so there's definitely no way I'll pass inspection anytime soon. It's getting very tiring trying this. Thanks for all the help though to everyone.

RPM WS6

iTrader: (3)

That's the one I'd go with. I've heard these mufflers before and they seem to reduce sound pretty noticeably. That might be worth trying.

dlandsvZ28

You install the Car Chemistry aft of the y pipe. I welded mine in aft of the QT cutout I also had installed. There is enough length aft of the y pipe for both.

I installed a Car Chemistry Insert with pipe with Jet Hots, ORY, and Magnaflow cats. It for sure reduced the rasp, but not completely. But now after removing the Car Chemistry tube the car is back to the Harley motorcyle sound when taking off all the way to about 3k...which I hate.

I took the CC off because some suggested it killed horsepower (by I recall 50 rwhp) with a test done at MTI. Did I dyno it...no not before or after. I also installed an ATI D1sc, another reason why I removed it if it really is a restriction.

Car Chemistry built a special one for me. Four inch diameter with 3 inch inlet and outlet. It is also coated (with a much better coating than the cheap coating on the Jet Hots that's flaking off bad). One would hardly think the Jet Hot's were ever plated.

I have about $1400 dollars in two catback systems (Borla and Magnaflow) installed on my car. Yeah...true duals get rid of rasp, but the only true dual system over the axle system is from Bassini ($949). If I go with the Bassini (that's nearly $2500 total for all three systems in parts and labor to get rid of rasp).

Probably the cheapest route for you is get a 3 inch CC insert, stick it into a 12 inch slip-on pipe (female both ends), band clamp it, do the test, and then yank it and put in a straight 12 inch pipe again. You can do all that yourself with a good hacksaw, some car stands, and two bandclamps. I would go with aluminized pipe for the 12-16 inch pipe or (stainless). An exhaust shop can easily expand the aluminized pipe to fit over the 3 inch catback pipe.

Redneck Z

iTrader: (3)

If your catback is clamped and not welded to your y-pipe it's easy. Just unclamp, insert and reclamp.