Libertariat

Just got my engine swap finally done yesteray and here's the setup:

H23A Engine.
Logic Tri-Y 4-2-1 Header
Vibrant 300 Cell metal core cat
2.5" Mandrel Stainless piping
18" SS 2.5" Vibrant Resonator
06' Si muffler

The thermal universal muffler I ordered was 18" on the oval, and too long. It's the same muffler used in the street systems for the full thermal kits. So the original plan was to ship the 18" back for a 14" and have that welded on. Now I'm having second thoughts about how to get it quieter.

Thoughts:

Longer resonator or glass pack (22")
Add a 14" Vibrant Ultra quiet resonator (if it fits)
Perhaps try another muffler?

Suggestions? The car is hitting 92-95 Db on the straights where I'm hitting the rev limiter in 2nd gear. I wound up using 3rd gear in the open parts to keep the exhaust tone down since the engine pulls really hard in every gear in the ITR transmission I've got bolted to it.

Thanks!!!

-Adam

Atmosfear

iTrader: (18)

I had a v-band turn down on the end of my muffler. Once I knew what side of the track the sound **** was camped at I would turn it the opposite way.

There are cheaper alternatives to a v-band that would achieve the same result.

solo-x

This has got to be the dumbest thing ever. Do you think the sound limits are there just to ruin your day? No, they are there because the neighbors complained. If you want to keep using your track you'll do the responsible thing and make your car quieter rather than try to beat the meter.

known

iTrader: (1)

add a resonator or like atmosfear said

I went with the longest muffler i could, im able to stay below the DB limits of RRR.



solo x really? go chase some cones

solo-x

Op, what are you using for an intake? My ITR will hit 96db with an AEM CAI, but won't get over 90db with the stock airbox.

solo-x

Known, you're a close minded fool if you think noise isn't a serious issue that affects us all. As for the cone comment, really? Petty.

known

iTrader: (1)

Close minded? lol ok auto'xer

racerdud17

acquire a new exhaust. such as an Apexi ws2. or get a better new muffler and longer resonator. ss piping is usually louder because it is a thinner pipe then most exhaust pipe. something suck as a mugen twin loop goes through the muffler twice making the exhaust quieter

solo-x

Thanks for proving my point.

Egezzy

iTrader: (2)

I had the same issue with a muffler not fitting.

I ended up getting a short blox muffler and a turndown. I have yet to cut the old system to put the new one on, but I think it should get me atleast 5-8db down.

Lol at the name calling. There are a few "pro drivers" that I look up to that used to "chase cones". Honestly, being behind the wheel, driving at the "limit" is always a blast.

known

iTrader: (1)

sensitive much lol

libertariat

22" magnaflow might work if you can fit it

dirty19

iTrader: (1)

Here we go again with exhaust this time....
Nobody searches do they?

If you had a bad *** exhaust like Harley, and me you'd have no issues whatsoever.
Search Redshift Motorsports...
We have probably the best, and adjustable (the ability to quiet it down)exhausts that are no longer on the market.
A work of art to say the least!

Libertariat

I'm just hoping the Thermal R&D muffler will clean up the exhaust not for sure. And if that doesn't do enough I'll slap on a longer resonator.



I've read a lot of the "quiet exhaust" threads over the years, and I still get really mixed information. Since autocrossers and road race folks actually have to deal with an actual decibel meter I figured this would be a solid place to seek out advice from people who have dealt with a similar problem.

Kiddies who say "omg my 3" Vibrant straight through was so quiet" - are a little difficult to place much trust in.

Atmosfear

iTrader: (18)

I understand the point you are trying to make, however some "neighbors" will complain about the sound of a rat pissing on cotton, and I can easily find examples of far "dumber" things that people have done to their cars.

Libertariat

I'd rather we not turn this thread into an autox vs. the world, or "how pointless decibel requirements are."

I can't do anything about the Atlanta Region decibel requirement, I can do something about my exhaust note.

Running the hotter parts of the course in 3rd gear isn't all that fun.

Abandoned Ship

I'll just leave my 2 cents here since i saw this on the FBGDD.

I ran a 2.5 inch mandrel bent exhaust on my b20 turbo setup, with a ES tuning oval muffler and a greddy resonator from a del sol exhaust, and it was no where close to the decibel limit i heard when i was at the road track. I ran that setup NA and it was just as quiet. Yes, i realize that your H23 will be a bit louder, but you will still be within reason.

ES tuning, and the Thermal mufflers are basically the same, so you'd definitely be just fine with one of those. The problem is fitting one under the back of a hatch. I had to trim my bumper just a tiny bit, or you have to run it pretty angled.

Libertariat

So you think the thermal muffler should tone it down a bit over the 06' Si muffler? The 18" was definitely too big, I'm pretty confident the 14" will be just fine.

I'm sure it will at least clean up the exhaust note, running a 2.5" mandrel exhaust to a tiny 06' Si muffler surely overwhelms it.

Abandoned Ship

It should, stock exhausts rely heavily on a cat and factory resonators to help keep them quiet. My s2000 had a race header, 63mm tp, removed factory resonators and even with the twin loop factory axle backs was loud as ****.

How the hell did you manage to get that giant *** muffler under your hatch?! i had a type-s axle back and that thing didn't even begin to fit.

What is the DB limit btw? You're kinda in a pickle. You might have to run a bigger resonator too. Sucks, but sound limit is sound limit.

My roommate had 3inch straight pipe with a ES tuning stealth on his car, but that was a turbo single cam. They are quiet, but I don't know how much different it would be since i know the turbo quiets things down a bit.

Libertariat

Actually fits just fine. Had to get it adjusted for the swaybar once I put that on.

I think the body is ~13" when I measured it, so the 14" oval from Thermal should fit as well.

Decibel limit is ~95, 90+ is the warning zone. I hit like 94.3 on my loudest lap.

Trying to decide if the 14" vibrant ultra quiet can just be added to my current setup:



I suppose I'll try the Thermal first and see how that goes. Their exhausts usually sound amazing, and they claim these univerals are the very same design they use for their CL and ST systems.

Abandoned Ship

you were hitting 94ish DB's on TWO resonators and a stock axle back?! You sure that's not a 15:1 race motor? LOL geez!

Libertariat

Haha. 300 Cell cat and one 18" resonator

I'm really thinking that Si muffler is the culprit.

Abandoned Ship

lulzing @ running a cat

yeah its gotta be, those things have rely on chambering, i looked it up after our fb convo, and no actual material.

If you could just knock off 5 db, you should be 100% fine.

Abandoned Ship

and LOL i was like wtf my post count is changing?! forgot i'm not in GDD.

AFAccord

I've done some swapping around with a vibrant flat black muffler, two vibrant standard resonators, a vibrant ultra quiet resonator and a couple of no-name 20"+ glass packs on my 2.5" setup with a e-cutout. I've had all the vibrant pieces installed at the same time, along with one glass pack, with the cutout at the end, just before the muffler. Yes, it was a mess, but sounded just how I wanted. I can testify that once I removed the Vibrant ultra quiet resonator alone, things got MUCH louder. I literally turned around after two miles and drove back to the shop to have it reinstalled. It really made that much difference. I highly recommend it if you can fit it.



***** video clip...
http://i80.photobucket.com/albums/j1...ackingout2.mp4

Libertariat

Holy wow. I was worried about that thing fitting. If the Thermal R&D doesn't tone it down for mt, certainly something to consider. I have found 24" stainless resonators which I could run over the 18" vibrant I have now. I'm thinking with the 0 sound absorption material the 06' Si muffler has, something with packing will really make a big difference.