So I just recently installed my rv6 HFCs and jpipe. After installing them I noticed the nasty rasp that I don't like. I wasnt getting it with my stock cats and jpipe. I only hear it when I'm in full throttle and vtech kicks in but I still don't want it and do not look forward to removing either the jpipe or HFCs.

https://acurazine.com/forums/car-parts-sale-361/3g-tl-magnaflow-custom-exhaust-pensacola-fl-818119/

This is the link to the cat back exhaust I have. All I did was put bigger tips on to fill in the opening for the type s bumper. Other than that its the same as when I got it.

I'm just wondering what modifications I can do to my cat back to get rid of the rasp.

I Hope someone can help and thanks.

 

Mods feel free to correct my title, please.

 

you can add another resonator

 

Would that quiet down my exhaust? since it would add restriction with a second one. I talked to richie from rv6 and he mentioned I can possibly go with a longer resonator depending the size of the one I have.

 

I had my non-resonated ATLP exhaust, and RV6 V3 J-pipe installed, and loved the sound. I then installed PCD's, and the "rasp" was/is terrible. I purchased a magnaflow muffler and cut my brand new exhaust to have it welded in. All that did was kill the beautiful tone of the exhaust, and make the rasp more pronounced. I had the muffler cut back out, and retraced everything I had done with the pcd and J-pipe install.

This noise is very pronounced above 3k RPM..

What I finally determined is this is caused from the mass flow of air bouncing off the stainless from the PCD. This is a phenomenon called "Tinny". I don't know if this is what you have going on, but hopefully someone that knows more than me can help you out.

 

yes i have experienced this rasp probably more than a lot of people because at one point i started with. no resonators 2 magnaflow mufflers. then i went to no mufflers just tips and no resonator both had crazy crazy rasp. then now i currently have 2 resonators with no mufflers . the only timne i hear rasp now is if i shift between 2700-3000 rpm. but any other time i dont get rasp any more. but what i hear more of now is the jpipe flex pipe rattle which doesnt realy bother me.

 

Add a resonator.

 

Will the resonator really be the fix for it all I have the same problem it's so bad!

 

a mid muffler may knock it down as well, smooth it out.

 

Done-taken care of for you.

 

Resonators are made for the sole purpose of calming down rasp and drone without cutting exterior noise too much. Throw one on, see how it does. I got an 18" for $60 and it killed my drone.

 

+1 with the resonator.

FYI resonators don't add restriction, they work by using a concept in physics called destructive interference. Mufflers are a bigger potential source of restriction as they reduce the volume of an exhaust note by implementing restriction. Not all mufflers are created equal though, so keep that in mind! It is possible to have a free flowing muffler; but just know that oem mufflers do use the restrictive chambered construction most of the time.

Rasp is caused by sound waves in an exhaust system clashing and creating a sound at a frequency that is uncomfortable to human ears (rasp).

A resonator uses destructive interference to have sound waves at opposite phases clash and therefore cancel each other out. This helps eliminate the sound being emitted at the uncomfortable raspy frequency.

Basic physics concepts can help a great deal in understanding the sound your exhaust creates! It isn't the answer to everything, we need R&D for that, but it helps enthusiasts like us solve some of the problems we encounter from our aftermarket parts

From the look of your custom magnaflow catback, the culprit could either be that small resonator or that peculiar Y-pipe. A long resonator and two short resonators work in different ways, so try to look up what each may do. You can also consider a different Y-pipe if it REALLLY bugs you I'm not guaranteeing you anything, just offering my two cents from my basic understanding of physics. Don't kill me if it doesn't work haha.

The J-series motor doesn't rasp as easily some other engines I know, so I don't think you'll have a hard time taming that beast. After my HFPC installation, I get a little bit of rasp going WOT somewhere in the 2500-5000k range. It's no biggie to me though!

In conclusion, I am with the others. Either add a second small resonator rear the current resonator or replace the current resonator with a longer one altogether.

Goodluck!

 

^good info

 

Thank you so much for the info!

 

Thanks for the lesson cuz I didnt really know squat about this subject and I will be doing some research to help me decide what route I go.

 

Mangaflow Resonator - $68
http://www.rv6-performance.com/index...d=12&Itemid=66

 

or try these Magnaflow#10436 or #12640

 

One of the two reason I refuse to get the PCD. I would never want to sacrifice the exoticness sound of my car. The second reason being that I don't want it to smell like rotten eggs. Ewww pweeeee, I have a $20,000+ car and don't want it to smell like some little $3,000 Ricer.

 

^ Your youtube videos lag.

 

it actually doesnt smell like rotten egg.
it smells like a motor bike.
or like a weed eater/whacker.

 

watch them in HD that seems to correct most the problems with most the videos, with the way youtube converts them.

 

Same here. I had the ATLP quad non-resonated catback and J-Pipe and LOVED THE SOUND. Its the PCD's.

 

this. you'll never have that rotten egg smell because there are no cats that can fail!

 

We've all told you amigo try putting some resonators on... find them round ones not the ones i have but round that can fit right in the fitment... And i bet it will help the sound a lot...


you got nothing to lose amigo...

 

Of course it's the PCDs, he'll I'm scared the HFPCs would even be raspy without another resonator.

 

hes runnin hfpc's and already has a vibrant resonator.

im currently in the same position, i have the same setup but an xlr8 catback and have crazy rasp!

 

^right there with ya man, just got an xlr8 catback as well and the rasp is horrible even after i cut into the brand new exaust and welded on the oem resonater running after the jpipe..not sure what to do at this point

 

I installed the rv6 v3 j-pipe and the xlr8 quad resonated exhaust on my TL. Sounded nice on the outside, but the drone and rasp was very annoying. I tried putting the cones in the exhaust tips, that help a little but under load and between 2-3k it was still to much for me. So I ordered the magna flow 12640 resonator/muffler. Things a monster, I didn't even think it would fit. Friend of mine came over today and we removed the old resonator, and tig welded the new one in place. What a difference, still a slight drone (90% gone) but that was with the radio off. No rasp, and still have the nice deep note on the outside. Definitely recommend for anyone with an aftermarket catback.

 

I think im going to do the same thing as u did and purchase the magnaflow 12640, the only thing im worried about it is rubbing when i drive because i car is slightly lowered just about flush with the wheels, will this be a problem? and how much bigger is this one over the stock resonater on the tl s?

 

Mine is also lowered 1" or so with tein springs. It sits a little below the frame. I search all over today for a speed bump to test it out, but could not find any. Do a search for the 12640 to see a pic, but the over all length is 33". Can itself is about 27" x 6" roughly. It tucks up in the tunnel very nicely, but hangs below the frame rails about an inch.

 

Ok cool I probably consider that one as long as I do have any problems speed bumps wise, whered u order it from?

 

Do not*

 

I am with you man. I never recommend these things. Just not worth it.


Anyway, we offer the resonator through heeltoe as well as an ATLP recommended part:

http://www.heeltoeauto.com/atlp-reso...-vehicles.html

 

The rasp isn't caused by the exhaust, as we have explained. The common denominator in all these cars with rasp is the PCDs. They make power but if you don't like rasp don't install them.

 

^doesnt make much sense to me tho why your exaust still sounds raspy if you choose the resonated option..i know rv6's exaust sounds perfectly fine with 0 rasp with just the base system followed by pcds and a jpipe.. for future refrence id reccommend making a bigger resonater to take care of any raspyness and tone down the sound.

 

You probably don't understand because I think a lot of people are falsely going on believing that resonators are designed to eliminate rasp. Resonators ARE NOT designed to eliminate rasp.

It is like saying a band-aid is designed to heal a cut. It isn't. Cuts heal better when they are clean, and that is what a band-aid does. There is a distinction there that seems superficial but is really important.

Rasp comes from the design of the system. PCDs, being that they are wide open right off the engine where there is normally the muffling of a converter there, create the raspy sound. We also know the design of the j-pipe does play a role as well, as evidenced with this video:

A resonator is an inline muffler that tones down the whole system. Therefore, it will reduce the sound of raspiness. But resonators are more designed to reduce resonation, or drone, insides the cabin. If you don't want a raspy exhaust, don't eliminate the cats. It is pretty simple. Resonators are merely a band-aid for rasp. They don't fix it. They at most reduce it.

 

I started out stock, then went with the resonated xlr8. Way to much drone. Carpoolers just bitched the whole ride, wife wanted me to park the car and used someone elses the first and only time she rode in it that way. So, I talked with mike at BillyBoat the builder of the xlr8 systems. He stated that the speed at which the exhaust is flowing slows due to the bigger less restrictive pipe. Basicly it needs back pressure to reduce the drone. He gave me some cones to stick in the tips to help increase the back pressure thus recuce the drone. He also said to try putting in a new J-pipe. I bought the RV6 j-pipe, no help.It added a little rasp. Then I installed the cones, that helped a little but not much. I then ordered the magnaflow 12640. A friend with a tig welder came over and we cut out the old worthless resonator, and installed the 12640. This fixed everything, every after market catback should be made with this pre installed. I even pulled the cones out of the tips. No rasp, no drone just a nice mellow deep note about as load as the road noise inside the car. Outside still has the nice deep note . If your not in your teens anymore, this is all you need. If your a teen enjoy your drone. Also, I have the tein lowering springs. So, I was worried about clearance. I found a tall speed bump and parked over it. I still have about 1.5" of clearance.

 

A 6x27" can under the car? A 12640 is not a resonator man it is a MUFFLER. That is huge dude. If you need something this size to reduce drone and rasp someone went wrong somewhere.

 

I had the same issue. I just added the Magnaflow resonator and a Magnaflow mid muffler. Rasp gone.

 

Then something went wrong with everyones catback systems because the is a ton of people on here complaining about the same drone. Seems the magnaflow 12640 is about the only cure.