Why is it that a bigger turbo and manifold cause the exhaust to sound like crap? I understand about the twin scrol design, and stock manifold quiets things down. But at 4000 RPM's I get a fart can sound from my muffler..

Who else has this problem after installing a bigger turbo and manifold, and what did you do to fix it?

I have been looking at a resonated test pipe, but dont want to impede performance that much as like I said, I only get the fart can sound at 4000 RPM's....

Nothing is rubbing, or hitting aything either...

 

I know you stated an aftermarket manifold...but I have to ask...is it a cast manifold, or a header/tube design? Everyone uses differently terminology, that's why i ask.

 

I have a cast manifold.

Which I would think would help eliminate the exhaust noise compared to a tubular ss manifold.

 

Bigger turbo causes differant sound resonant (more or differant exhaust flow from engine), and if it happans to be the right frequency and tone you'll get the farts lol

I have a resonated test pipe on mine, In my opinion, it is worth a couple horse to have it not sound so loud, or worse sound like ****

 

jsut get a bigger muffler and you will be golden
dont run farn can round stylr mufflers if you dont want to to sound loud and crappy.
run the largest magnaflow oval muffler you can fit and it will sound quiet and great

 

Yea, I would like to stay with the buschur bullet muffler as it has really good flow. What resonated test pipe are you using? And it s it straight through or does it have perforated holes inside it like the TTP test pipe does?

I love the sound of the exhaust, just at 3900-4000 I get the fart can sound...its very strange. I guess like you said the tone and frequency is just right at that point and it produces the infamous civic muffler sound.

 

So here are what looks to be all of my choices...

Megan Racing Resonated Test Pipe


TTP-Engineering Resonated Test Pipe (this piece is has perforated holes inside the pipe)


AMS Resonated Test Pipe


From the looks of these, it looks like the AMS piece will do the best job in eliminating extra raspy sound, but will reduce the most flow....

 

maybe we could get AMS's opinion on the use of a resonated test pipe and estimated loss in power..

 

Good idea

As far as the first two test pipes, mine looks like both lol, but is the megan one, it is 3" all the way through and has perforated lining along the inside

I've never seen that ams one

 

The JunB.L car with a GT35R does not sound like crap. They are using of course the JunB.L catback exhaust. It is not as deep as my stock turbo equipped car with the JunB.L exhaust although it does not sound like a raspy honda.

You might want to consider a different muffler as that will net you the largest difference. If a resonated pipe takes away 2whp a muffler might take away 3-5. Nothing you would truly feel.

 

My AMS exhuast has a Farty sound, and I have the stock turbo and manifold.

 

Ill tell you what....give me your turbo setup and you will get rid of the fart can sound


my buddy had the same problem w/ the sound when he put on his AMS 50trim kit so he installed the AMS resonated test pipe. It quited it down significantly and he still put down some great dyno #'s on a low reading mustang dyno

 

yea, i think I am going to go with the ams resonated test pipe as it looks to be the best bang for the buck as far as eliminating my fart can sound at 3800-4000....

My exhaust sounds great until that RPM point...

 

haha, I wouldnt know what to do with myself with a stock turbo...I would be in boost all day long, everywhere I go probably...haha

 

I have the AMS resonated TP on my EVO and it does not restrict flow at all. Its 3" diameter piping throughout with no- neckdowns or anything....

The muffler looking section is what muffles the sound down a bit...