I am well aware that the quickest way to make power on a turbo car is from the rear of the car forward. I know that a full 3" catless exhaust would definately recover some HP.

That being said.... I want my EVO to be quiet... I dont mind the spooling sound but I dont want loud exhaust.

Outside of installing a dump......what can I do to the car to keep it quiet yet get more power out of it? Can I get a stock dynoflash just to lean it out? Will cranking up the boost help even with the bottleneck?

Is there an aftermarket better-than-stock flowing catback that is still quiet?

Please send some suggestions my way.

Thanks,
Darth

 

WORKS TBE (DP, HFC, IP) with StealthWorks muffler is almost as quiet as stock and also flows way much better than stock. Maximum flow while maintaining stock noise level and stock look to keep from getting pulled over.

 

Links?

 

Well first thing would be is to get a MBC and set it to 21 lbs. You'll see a nice gain out of that. Next would be to get a Flash or some type of A/F control to lean out the mix.

As for sound -- how quiet do you want? Nothing aftermarket is going to be as quiet as stock -- atleast that I know of. Every aftermarket is going to have better flow and less restrictions so it is going to be a bit louder. As for a good exhaust that isn't loud as the others I would say Megan -- some people poo-poo on it. I personally love it.

 

RMR catback is not very loud.

 

Works parts

Here ya go

 

Search. There alot of threads on these topics. Have a nice day.

 

Well, if you really want to keep from making noise, then I suggest keeping the stock exhaust and doing this:

- Drop-in filter (K&N or others)
- MBC (20-21psi) + boost gauge to monitor safely
- JDM MR BOV (to hold that boost efficiently, but not be obnoxious)
- S-AFC (w/wideband O2) + injectors to allow for greater tuning latitude
- 10.5cm^2 hotside replacement for your 9.8
- Lower intercooler pipe
- Fuel pump (walbro 255lph)

You can do all this and not be any louder than stock except for that which is caused by increased air flow (more hp). With some good tuning and driving, I'd bet you can do low 12s with this.

 

One thing to be aware of is exhaust systems that use a silencer to keep them quiet. I think you'll see this "feature" in JDM exhausts for the most part. Most silencers design are so restrictive if you drive around with the silencer in place, you have worse flow than stock. My guess is people just put them in when they need to pass inspection, and then put them back on the shelf.

Edit:

Here's a link to a Helix with a silencer installed:

https://www.evolutionm.net/forums/sh...haust+silencer

 

Greddy EVO 2 is pretty damn quiet. All of the EVO 2 exhausts are below 95dba.

 

I have a hayward & scott exhaust. The system is a 3" collector that leads into a 2.5" TB exhaust. I used to run a 3" TB exhaust with high flow cat, and when I switched to the H&S exhaust I noticed an imediate increase in low and mid-range torque.

It's completely modular, you can use the stock cat if you must, and the stock muffler if you must.

Even when running catless, the exhaust is super quiet. When running the stock cat, the exhaust is barely louder than stock

http://www.haywardandscott.com/

They are kind of pricey, but IMHO, well worth it.

 

edited

 

http://www.z1auto.com/prodmore.asp?m...ust&prodid=705

i think the Fujitsubo is the quietest exhaust their is for an EVO.....it's not cheap but if you want an exhaust this is no louder the stock is this what you want......

 

Hks hi-power is quiet

 

everyones idea of quiet is different....if you want a new exhaust that will give you more power but not be louder then stock get the Fujitsubo.....i heard it with my own ears...just wish i had the money to get it


found a sound clip for you