Hey all,

I currently have a 3' thermal exhaust with a test pipe and a type R header on my all motor b16. Before anyone starts in on the too big/no backpressure conversation let me just say that this is not what this post is directed at, and I made significantly more power upgrading from 2.25' to 3'. With that said, over the past few weeks the exhaust has become increasingly loud. Loud enough to warrant a ticket almost every time I drive it (3 tickets in the last month). It sounds like i'm running an open header at the moment.

I checked underneath the car to determine if there was an exhaust leak. I wasn't able to find anything. A buddy of mine mentioned that perhaps the muffler has broken in a bit (I've had it for roughly 8 months now).

Does anyone know any way I can quiet it down. I brought it to a muffler shop to see if they could install a cat. They were having trouble with the fact that the type R header has a 2.5 inch collector and the thermal has 3 inch exhaust flange. First, will installing a cat significantly quiet down my system, and two where can I find a good cat that will work with my setup?

Additionally, has anyone experimented with creating a silencer for the thermal or any other unit? A friend of mine and myself considered this as well.

Finally, does anyone know any quick or band-aid fixes I can use for the time being? This is a daily driver and I have been hitching rides with my roommates and its becoming a pain in theirs and my ***.

Thanks a bunch,

Steve

 

You could get a resonator or two

 

I don't think the 3" Thermal has a resonator. A cat will definitely help quiet it down, but the straight through muffler isn't helping with noise output.

 

The EF system does have a pretty decent size resonator that sits underneath the cargo area right by the gas tank. Combined with a cat maybe it will quiet it down a lot. Any idea where to get a cat that will convert from 2.5 to 3 inch?

 

Me and my friend thought about this. My only concern was cutting apart a stainless steel system to put resonator in the exhaust channel. However, If it didn't work I would lose all resale value. Thank for the suggestion though

 

There isn't any secret to quieting down an exhaust.

Either:

A) Get a bigger muffler, maybe a Mugen Twin-loop design or some type of Oval.

B) 20" Resonator or larger

C) A combination of A & B

There's no "Band-Aid" fix. You're not leaking any exhaust, you just have a loud-*** exhaust system.

If you add a Cat, you're going to start to cap off any performance gain your 3" SS exhaust system is giving you.

Or live with the tickets and have a stock exhaust you can put on for the "fix-it ticket" dates.

 

That part under the gas tank is the muffler. A resonator will usually be in the B pipe.

You can always order a 3" cat, and just get a reducer. They are a little pricey though:

http://www.burnsstainless.com/rd-250-350-18-304-s.aspx

 

You could always contact Dave at SMSP and have him make you a custom cat. It will flow well and help quiet the car as well as fit properly.

 

I was just looking into resonators. Do you have any experience with them? I was looking here

http://www.sfxperformance.com/parts/VIB1142.htm

I figure maybe one or two of these could significantly quiet it down. Or do a combination of the cat and the resonator

 

+Resonator & cat, you can cut the outlet on the cat and get a taperd peice of SS from 2.5in to 3in and weld your exhuast to the cat. or custom cat from smsp like someone said

 

A good resonator will make a significant difference. You can install it pretty much anywhere along the exhaust from behind the collector to in front of the muffler. Welding it in is not hard and any exhaust shop should be able to do it. I popped one in yesterday in about 30 min from the car rolling up to my house to it driving off.