Custom Exhaust
 

I got my custom exhaust done today for my 2000 porsche boxster. It has dual magnaflow mufflers. After driving it for a while, i noticed that the volume outside was perfect, but the volume inside the car was so deep toned and loud. Anyone ecounter that problem after getting a new exhaust?? any idea's on how i can lower the volume?? thanks

Magnaflows and custom exhausts are a recipe for loudness... You could add some resonators to lower the volume.

Resonators
 

Don't i need my CATS to pass california smog tests though??!!

I think by resonators, he means sticking drag pipe inserts into the tips of your muffler to help drown out the drone. The factory exhaust is designed to be rid of any annoying resonance drone that you are experiencing inside the cabin. Your aftermarket setup is not designed specifically for the Boxster, and probably utilizes two separate universal fit muffler cans welded together with a crossbar. These might sound nice on the outside, but will give you really bad interior drone that will drive you batty after long drives, give you headaches, or worse, even hearing loss after extended use.

The only sports exhausts I know of that don't give you that annoying interior resonance are the factory Porsche Sports Exhaust (PSE), the Dansk Pressed Sport exhausts (as these are made in the same shape/design as the factory mufflers), or the DIY modified factory exhausts made by welding bypass pipes connecting the muffler inpipe to the tips. All other sports exhaust have some sort of interior cabin resonance, but many live with it by keeping the revs of the engine higher in the rev range where the drone is not noticeable.

Sorry, not much you can do about the drone. If you had done some research you would have learned that several of us have built custom exhausts (for various reasons) and yes, they all drone. Sorry.

Your pretty much out of luck.

On typical front engine cars, people add resonators to get rid of drone.

(looks like a glass pack, ex. you'll see 2" piping bulge out into a 12" section of 3" piping then back down to 2" piping. possibly multiple shorter resonators.)

They act like mini mufflers.

On a Boxster, you just don't have the space to add a few of these.

I plan on making my own using borla mufflers, but it will be clamp on rather than welded so i can change mufflers in the future if i wish to.
Anyone know of any other muffler brands that will sound really good? I would like to get somethign that sounds like ferrari-ish

pixi glass shield
 

do u think, that if i were to build some sort of glass shield in the trunk that would help? or anywhere else

Bleh
 

:o I don't know ANYONE AT ALL HAVE A SOlUTION to getting rid of the drone in the cabin, i will forever be thankful

You can add some Dynomat behind the belt cover. You know the shield that is behind the seats that gives you access to the serpantine belts.
http://i5.photobucket.com/albums/y15...sh/4lpgsgj.jpgIf you add some Dynomat there on top it should make the noise level lower. :cheers:

Yes. What you have is called drone. How much did you pay for this custom job? Fabspeed has a high performance system that they guarantee is 50 state emissions legal and does not have drone. And I hear it sounds great. I plan on buying it soon.

Which Ferrari? A flat-12 Ferrari, a V-8 Ferrari or a V-12 Ferrari?

You're not going to be able to make a flat-6 sound like any Ferrari. Period. Sorry. Just love the sound you have.

In terms of the drone, no amount of dynamat or shielding is going to eliminate the drone. You need two things - carefully thought-out chambering and exhaust path length. Most of us do not have the resources or experience to design something like this.

4 bills :)

Well i dont expect it to sound just like one but wasnt there thread not too long ago here for a certain brand of exhaust that was super pricey for a 987 and someone said it sounds like a ferrari and someone else said its cause the manufactor of that muffler also makes the mufflers for Ferrari's... Wish i could see how they looked inside, which would help alot.

I'm sorry - regardless of exhaust system - if somebody ever tells you they have a Boxster that sounds like a Ferrari, instruct them to locate said "Ferrari" which bears the same sound and have them demonstrate. Ain't gonna happen.

A flat-6 can have its own distinctive wail (ever hear a 996 GT3 with straightpipes at redline? Amazing) but it sounds nothing like any Ferrari.

/rant.

i dunno man, i get annoyed over the sound of a ferrari after a while. But don't get me wrong, i love the car. I like the Lamborghini Gallardo sound too :)

Cabin Droning Driving Me nuts!!!! SOmeone please come up with a solution, to allow to me both keep the exhuast and muffle the sound in the cabin

put the top down (and turn up the stereo)

There's no way you're gonna get rid of that drone. But...to keep the exhaust and muffle the sound in the cabin, you can....

....just wear EARPLUGS when you drive. At least you'll sound cool to others around you. :D

You're not going to solve the drone. Sorry. It's just not going to happen.

I heard of someone putting header wrap around their mufflers and they said it helped the drone by about half. Might as well give it a shot.

wooah Can you find me some more info on that!! i will forever be in your debt thanks

Boxster sound llike a ferarri? Not going to happen. Flat sixes and V-12's 10'sr 8's won't sound similar.

header wrap? here ya go:

http://www.jscspeed.com/part_pictures/tt_11001.jpg

http://www.jscspeed.com/index.html?/univ/thermotec.htm

or maybe you could try this "super sonic acoustical mat"


http://www.jscspeed.com/part_pictures/tt_14700.jpg

"This high quality mat offers superior sound dampening control to reduce road noise, rattles, engine noise, and any other noises that are bothersome. The high density polyethylene film with an aluminum foil composite is abrasion and tear resistant. The gray film provides structural integrity & strength, allowing the material to bend, move, & return to shape even under tension forces. The product is 70 mil in thickness, contains a high temperature adhesive backing, and is easy to trim & fit. The rubberized compound is applied with the high temperature adhesive to absorb all those out of control noises."

I don't know...this sounds pretty Ferrari-esque to me:

http://www.kreissieg-usa.com/video.php?video=bx060113tuka02.mpg&desc=F-1%20Mode%20Highway%20Pass%20By

Sounds kinda similar I guess. Where is a sound like that under 2k?

Not sure because I don't know anyone personally that has that exhaust system. It is mucho expensive ($5000), but probably the most similar in sound to a Ferrari I've ever heard without having to buy one.

do you think the header wrap will reduce the droning in my car?

Dude...sorry to say, but give it up already....NOTHING is going to work except you pulling out the muffler and installing a factory Porsche Sports Exhaust, modifying the stock muffler, or buying a Dansk pressed sports muffler. Those are the only exhausts that don't drone at all.

The design of the location of baffles and pipe length INSIDE the muffler is what cancels out the drone. Engineers spend a lot of time figuring this out, and your universal fit Magnaflow muffler cans are not designed specifically for the Boxster, so it will give off that annoying resonance. No matter what you do to the outside of the muffler, it will not help unless you wear earplugs.

Ditch that "Custom" exhaust system and buy the Fabspeed or Porsche Sport exhaust. It will be cheaper in the long run. By the time you wrap your headers and sound proof your firewalls and buy your ear plugs you will be at the cost of the Fabspeed. They guarantee no drone so if you get drone it's their problem to fix not yours.

I hate to tell you, but it will likely get worse. It takes a little while to break-in your muffler - it will get louder over the next month.

Just go with straight pipes...

They sound amazing, they are loud!!

http://www.youtube.com/watch?v=M1VI-rTaUmU

This is a exhaust setup with the bypass pipes, have the guy who built that custom setup for you do this and change the tips to what you like.


http://www.youtube.com/watch?v=EEPv_l6GBfw



My favorite video with current setup.
This is me approaching from about 1.5 to 2 miles away.
You can hear the car at full throttle in the distance but i had to back off...i was hiting going way to fast for public roads.

There are a few other videos with the new set up in different situations.


http://www.youtube.com/watch?v=Pw9bRcdOj-Y


By the way right now the car has stock cats, aftermarket headers, muffler and a supercharger. There is another phase of mods that are more agressive than what i have now.

Have a great day,
gary

Gary, I don't doubt that the straight pipe set up sounds loud, but this guy specifically is looking to tone down the resonance/drone in his car, as it is driving him crazy. I doubt a straight pipe set up would help tone down the drone, no? ;)

Magnaflows or most american brand mufflers=drone issue, plain and simple. Only way to turn it down is with Resonators(definitely wont work in most porsches bec. of the limited space) or replacing your mufflers.
IMO, the more highend european made mufflers are your best bet when you dont want the interior drone issue. I have a BRABUS exhaust with Resonator deleted in my MB E55 and there is absolutely NO drone even with the resonator delete mod.

The straight pipes where so LOUD i did not hear any drone, or my, cell phone, myself thinking....

The straight pipes where tounge in cheek, the other two options where realistic options.

The current setup i have has no drone, its actully to quiet for my taste and i may be looking for a used GHL.

The setup with the bypass pipes sounded GREAT but my tips where not the most attractive.

BTW Boxtaboy..i did get you wink. I love sarcasm.

Have a great day

"...so loud that you didn't hear any drone or yourself thinking." That is too funny. :cheers:

I've actually driven a GT3 with straight pipes before, and the sound ROCKED. Problem was it rocked the entire street so much that the neighbors came out to yell at me. LOL

the way i did my exhaust mod i dont have any drone in the cabin.
took it autocrossing this weekend with the guys, even more impressed and everyon gave me compliments on the sound.
plus it cost me under 50 bux
and i can close it, making it 100% stock sound wise, or open it partially.

False.

It has nothing to do with the country of origin of the muffler. It has everything to do with the construction of the overall exhaust system. The factory system is extremely complex, with tuned chambers and absorptive materials to cancel specific frequencies. The cheap custom exhaust that a local shop can build you doesn't have these designed-in features, so in the case of a Boxster it will create unpleasant tones. Simple as that.

Fixing the problem is far more complex. But it has nothing to do with the mufflers being "Amiercan." :rolleyes:

All I said was I saw where a person on a website with an aftermarket exhaust wrapped header tape (or some other varient) around the 2 mufflers. He said it helped. I would believe it due to the absorbing properties of the tape changing the resonant frequency of the metal. Do I know for a fact, no. But try it... you got nothing to loose but a couple bucks.

Where,
Since you live in the same city as I do, and may not mind visiting my facility in Chino, feel free to stop on by, so that I can take a look at your system. I may have a solution for you.

I just made a custom prototype unit that does not have the problems you have encountered...nonetheless, I am curious to your DB level with the current setup. Let me know!