What kind of custom exhaust should I do?

[wan2play]

Hey, I'm Paul and I'm new to the A6 forums. I had a 2000 A6 back in May, but it was stolen from me and found a week later totaled. Took me awhile to find another BLK on BLk A6. However, by chance a rich man I know was moving away and needed to sell his six speed, 2003 A6. Picked it up for 11,500. Only has 55,000 miles on it.

I recently purchased a RS6 spoiler, dummy shark fin, and a set of piggies. Still looking for a ECU, but no luck thus far. I can't seem to find the rims that were on my 2000. I was told they were a extremely rare set of Rs6 9 spoke, southside edition rims, powder coated black. Looked sick. Now, I have regular 5 spoke Audi rims... :(:(:(:

Enough of my background, lets get to the important stuff. I'm in search of some ideas for a custom exhaust system. Not trying to go 3 inch, but I do want it loud and deep sounding. I don't want the raspy sound of magnaflows. I want a Borla deep sound. What do you guys think of these ( http://cgi.ebay.com/ebaymotors/Borla...Q5fAccessories

I really need some help designing my setup, because when going custom you never know how its going to sound. Any suggestions on what to buy and what to tell my mechanic?

Thanks for your input guys.

[oc-drop]

I haven't heard many but magnaflows but here is an ok youtube vid of a s4 2.7t w/ borla if you haven't already heard it

http://www.youtube.com/watch?v=aEc4AR0Py9s

and another w/ 2.5in http://www.youtube.com/watch?v=knslbkWuoP4

[jstcalmebatman]

pardon my noob question but what are piggies?

[wan2play]

They are your stock down pipes, but with gutted cats and pre-cats. You need to relocate the O2 sensors not to throw a error. CELiminators. One quick search and you'll know all. Gives an extra 25-40 hp all dependent on the car and mods.

[wofman]

there are a couple threads in last several months on here worth reading - covers most you need to know or look into. (search "exhaust" and yu'll find 'em) Botom line: Unlike S4, not much aftermarket exhaust for A6 2.7. APR, Milltek, custom.

Good luck and welcome!

wofman

PS -- GREAT deal, way underpriced if in good condition. Post pix...

[Kievskiy]

Like Warren said, just search, it all depends how much money you want to spend and what sound do you want, folks who had APR said it was quite, so it depends what do You want.

[wofman]

also, no point going more than 2.5"; and problem with custom is what you said -- you don't know ahead of time unless it's modeled after something known; there are lots of sizes for components -- resonators and mufflers -- so there is no "one" sound for M-flow or Borla. I like Milltek and APR, but expensive.

[wan2play]

Thanks for the advice guys. I did search "exhaust", read all the previous threads related to my questions, and I feel that I need to gather some more info. I was hoping that maybe someone new would post a new informative opinion, which might shed more light on the subject.

Does anyone know anything about the mufflers in my link, or have something with the same dimensions?

[2.7tDallas/JonD]

Hey, I'm Paul and I'm new to the A6 forums. I had a 2000 A6 back in May, but it was stolen from me and found a week later totaled. Took me awhile to find another BLK on BLk A6. However, by chance a rich man I know was moving away and needed to sell his six speed, 2003 A6. Picked it up for 11,500. Only has 55,000 miles on it.

I recently purchased a RS6 spoiler, dummy shark fin, and a set of piggies. Still looking for a ECU, but no luck thus far. I can't seem to find the rims that were on my 2000. I was told they were a extremely rare set of Rs6 9 spoke, southside edition rims, powder coated black. Looked sick. Now, I have regular 5 spoke Audi rims... :(:(:(:

Enough of my background, lets get to the important stuff. I'm in search of some ideas for a custom exhaust system. Not trying to go 3 inch, but I do want it loud and deep sounding. I don't want the raspy sound of magnaflows. I want a Borla deep sound. What do you guys think of these ( http://cgi.ebay.com/ebaymotors/Borla...Q5fAccessories

I really need some help designing my setup, because when going custom you never know how its going to sound. Any suggestions on what to buy and what to tell my mechanic?

Thanks for your input guys.

You can only flash the ecu. replacement is hard due to immobilizer

[2.7tDallas/JonD]

also, no point going more than 2.5"; and problem with custom is what you said -- you don't know ahead of time unless it's modeled after something known; there are lots of sizes for components -- resonators and mufflers -- so there is no "one" sound for M-flow or Borla. I like Milltek and APR, but expensive.

I think that is incorrect

The exhaust on our cars are almost a straight shot back from the cats with two easy hanger points

My suggestion is 2.5 to 3" all teh way back to magnaflows.

Search on AW for mor einfo

[wofman]

what is incorrect? there are a lot of resonator and muffler sizes and configurations. Sound will vary accordingly. There is a reason no exhaust systems for 2.7 are larger than 2.5" -- what is point of 3"? Am I missing something?

[wan2play]

I think that is incorrect

The exhaust on our cars are almost a straight shot back from the cats with two easy hanger points

My suggestion is 2.5 to 3" all teh way back to magnaflows.

Search on AW for mor einfo

Ah, so from where would I start the 3 inch piping? No catylic converters or resonators too?

I don't think I'll come close to passing emmisions. I have gutted piggies and I want str8 pipes. They'll laugh at me. I'm not really worried about that, but does anyone have any suggestion in making it emission legal?

[cowboy]

( there are a lot of resonator and muffler sizes and configurations. Sound will vary accordingly. There is a reason no exhaust systems for 2.7 are larger than 2.5" -- what is point of 3"? Am I missing something?)


I have often wondered that two, because when i had a 944T the best setup was 3inch and the porsche only has a 2.5 liter four cy.

[wofman]

"Piggies" means different things to different folks. You mean gutted pre-cats and cats (ie no emission scrub) or do you mean VAST Piggies with high flow cats? To scrub emissions you need cats (high-flow for performance of course). To gain power of gutted cats and "fool" the ecu b/c no cats (and pass test in most states if I understand) you need to get rid of cels. Move the O2 sensors (or program around them), use "celiminators". So it depends on what you mean by piggies, what you mean by "legal". BTW, VAST piggies include mod to address O2s and CELs and be legal. AWE also ensures no problem with their cats and O2s.

As for "straight back" that is from the cats (gutted or otherwise). No cats and no resonators and no mufflers(?) would be one awful, loud approach. And definitely illegal. 2.5 pipes, no resonators and Magnaflow mufflers would be louder than I would want. Dallas does not agree. Bandito and Endee did systems close to this, but used resonators and/or x-pipes.

I thought you said no to "raspy"?

[wofman]

( there are a lot of resonator and muffler sizes and configurations. Sound will vary accordingly. There is a reason no exhaust systems for 2.7 are larger than 2.5" -- what is point of 3"? Am I missing something?)


I have often wondered that two, because when i had a 944T the best setup was 3inch and the porsche only has a 2.5 liter four cy.

I think APR addresses this on their website (maybe I asked in email, don't recall) but 2.5 was found optimal for downpipes and catback.

[TWINTURBOA6]

Don't do aftermarket/custom!! there's really no development and research in a custom set up... you should save up and go milltek or APR!!! PS you can always resell an expensive apr or milltek exhaust!! It's definitly worth it! you're building an Audi not a muffler shop acura integra - no offense to anyone with an integra...hope I didnt sound to snobby

[pit viper]

Don't do aftermarket/custom!! there's really no development and research in a custom set up... you should save up and go milltek or APR!!! PS you can always resell an expensive apr or milltek exhaust!! It's definitly worth it! you're building an Audi not a muffler shop acura integra - no offense to anyone with an integra...hope I didnt sound to snobby

"Development and research" into an exhaust setup for a turbo motor is not quite the same as for an N/A motor. You don't really have to worry about scavanging, etc....

With a turbo, generally more is better. The bigger, the less backpressure, the faster your turbo spools, the more it can flow. However, you have to be moving a certain amount of air before a given larger diameter is really going to benefit you, and the bigger the tubing, the more expensive it is.

I saw gains on my SRT-4 stock going from the 2.25" piping up to a 3". The more power you make, the more it helps.

[doobiesdaddy]

Ah, so from where would I start the 3 inch piping? No catylic converters or resonators too?

I don't think I'll come close to passing emmisions. I have gutted piggies and I want str8 pipes. They'll laugh at me. I'm not really worried about that, but does anyone have any suggestion in making it emission legal?

I have APR downpipes and high flow cats to a 2.5" straight pipe all the way out...no mufflers and it is awesome!
I passed the smog check here in California with that set up

[2.7tDallas/JonD]

what is incorrect? there are a lot of resonator and muffler sizes and configurations. Sound will vary accordingly. There is a reason no exhaust systems for 2.7 are larger than 2.5" -- what is point of 3"? Am I missing something?

There actually are NOT a lot

There are a couple of sizes of magnaflows that will fit in place of the stock in round or oval, and any resonators can be put in place of the stock ones, or you can just do without.

I went many miles with magnaflows, and then found a good deal on an RS6 center section, so I added that becuase I do a lot more highway driving now.

I have done straight pipes (loud, but fun), magnaflow only (sounds fine to me, YMMV) and even glass packs (woo hoo - took em back to the 60's)

At the very least - every a6 2.7t owner should have the centor resonator removed and pipes welded in. It removed 15 lbs, only a minute difference in sound, and make the car run cooler

[2.slowT]

Don't do aftermarket/custom!! there's really no development and research in a custom set up... you should save up and go milltek or APR!!! PS you can always resell an expensive apr or milltek exhaust!! It's definitly worth it! you're building an Audi not a muffler shop acura integra - no offense to anyone with an integra...hope I didnt sound to snobby

Do you know what you are talking about?

A custom setup not only sounds awesome but will give great flow.

You'll spend 1500+ on name brand and my 500.00 exhaust will sound better ;)

[Kievskiy]

^ lol, thank you, i was about to say that, funny how people are against custom fabs on Audis, so if custom fab is good for integra is not good on Audi, LOL, why waste money when you can get better rresults going custom.

[wofman]

There actually are NOT a lot

ovals, rounds; varying diameters, different lengths; perforated, louvered, baffled....

2.25" is what APR and Milltek use; even RS6 only goes to 2.5" -- suggest you ask APR why nobody goes past 2.5; even S4 only uses 3" for combined exhaust pipes set-up. 3" for 4 cylinder turbo sems silly, but I'm no engineer....

[4point2]

2.25" is what APR and Milltek use; even RS6 only goes to 2.5" -- suggest you ask APR why nobody goes past 2.5; even S4 only uses 3" for combined exhaust pipes set-up. 3" for 4 cylinder turbo sems silly, but I'm no engineer....

sorry to jump in here, but does that mean that I should be looking at a setup over 3" for my N/A 4.2 V8?

[wan2play]

So, I decided to tell me exhaust guy, "I want 2.5 inch piping straight through to one resonator and to a borla muffler". Or, say "F it", "Just make it straight through to the mufflers?
Link to Muffler > http://www.wickednicky.com/borla-mufflers-pro-xs.html

Offset/Offset or Offset/Center?

Any suggestions for a 4 inch tip, if one would even fit?

[2.slowT]

I think you want center/center. I know a couple people have tried the offset style and both said they would go with center if they did it again.

I think magnaflow has a 4". To big IMO, but by friend has it on his AR.

[oc-drop]

magnaflow dual round tips are sexy as fuckkk

i gots mine

[2.7tDallas/JonD]

Don't do aftermarket/custom!! there's really no development and research in a custom set up... you should save up and go milltek or APR!!! PS you can always resell an expensive apr or milltek exhaust!! It's definitly worth it! you're building an Audi not a muffler shop acura integra - no offense to anyone with an integra...hope I didnt sound to snobby

It's pretty simple

On an S4, with lots of bends, and strange fitment, tuner exhaust are worth it.

On an A6, where there is only 2 bends in the entire system ( at the rear ), and otherwise it si a straight shot, a tuner system is a waste of money

[audirs]

ovals, rounds; varying diameters, different lengths; perforated, louvered, baffled....

2.25" is what APR and Milltek use; even RS6 only goes to 2.5" -- suggest you ask APR why nobody goes past 2.5; even S4 only uses 3" for combined exhaust pipes set-up. 3" for 4 cylinder turbo sems silly, but I'm no engineer....

i think the reason no one really does 3" back is because of fitment. it would be extremely hard to fit 2 3" pipes going back in an s4. they were BARELY able to do it on my a6, they ended up having to like weld the 2 pipes together just to get them to fit up there.




pit viper has it spot on. the bigger less restrictive exhaust will yield the most gains.

"Development and research" into an exhaust setup for a turbo motor is not quite the same as for an N/A motor. You don't really have to worry about scavanging, etc....

With a turbo, generally more is better. The bigger, the less backpressure, the faster your turbo spools, the more it can flow. However, you have to be moving a certain amount of air before a given larger diameter is really going to benefit you, and the bigger the tubing, the more expensive it is.

I saw gains on my SRT-4 stock going from the 2.25" piping up to a 3". The more power you make, the more it helps.

[audirs]

sorry to jump in here, but does that mean that I should be looking at a setup over 3" for my N/A 4.2 V8?

i wouldnt think so. i think you could go 3". the only thing i heard about n/a motors is you have to be careful about backpressure. typically i heard people just buy vendor pipes since they are engineered properly for the n/a motor and dont tend to compromise back pressure and such

[pit viper]

With an N/A V8, I would spring for a tuner exhaust setup. You want some backpressure, they can use scavanging to good effect, etc... A lot more engineering involved when you're not forcing air through with a turbo or supercharger.

[wofman]

FWIW -- I looked into custom, had spec'd one out based on input here, discussion with very experienced modder-eng and cautionary feedback from M-flow dealer who does both components and systems. I ended up buying a used Milltek when it surfaced at 11th hour. Glad I did.

PitViper - I think you're right about (1) limit at which diameter stops making any difference. And why fill some volume prior to evacuating? The real eng issues are with downpipes, not catbacks anyway (and now that I think about it, it was 2.5 downpipes where APR did the eng evaluation for "optimal" size) and (2) N/A is where evac issues arise. That's why some use x-pipes, for example, but you don't want colliding flows with turbos with exhaust already spinning back.

4point - if you're reacting to my comment about 3" on S4, that is for both sides combined into one catback pipe.

Audirs - you can't get "less restrictive" than free flow and there's no point past 2.5 according to engineers I spoke to.

I had planned on similar to Endee, but without x-pipes -- 4x18 resonators, 5x8 oval mufflers (18L). You can get shorter on each item for less sound reduction. Bandito went with round mufflers (louder) and chose 6x14. Definitely center/offset on the oval mufflerss. I also like oval tips. Saves $ vs. "systems" but by definition you don't know what it will sound like unless somebody else does it first and you drive it, experience whatever drone might occur. And you still have issue of ensuring proper installation, no vibrations, etc. (Not rocket science but an issue.)

Last point - free flow cats definitely get louder after some break-in period.

I'm done. Drive fast.

[wan2play]

Geez, all I asked for is your opinions on how I should get my exhaust done, and you guys got into this whole other thing about who knows more than the other. Everyone's opinion has as much value as the next. I took all your opinions equally.

But, I still have one question unanswered. Do any of you actually have a custom exhaust set up which might resemble the one I'm going to put together?

[wan2play]

Everyone's opinion has as much value as the next. I took all your opinions equally. Wofman, your a knowledgeable man, who tries to get an answer for everyone, no matter how far out of your way it is. I respect that. Audirs, I like the way you question the fact that a 3 inch exhaust may have its benefits. The point you made about the A6's exhausts being pretty much straight back, makes the assumption that a 3 inch system might have its benefits. It really had me considering a straight 3 inch exhaust.

JonD, thanks for straightening out my ECU question. Your idea about 2.5 inch to 3 inch is probably the way I am leaning towards. Can you elaborate on where the 2.5 inching starts and where the 3 inch piping starts. And of course if I would add a resonator to this setup, where would be the optimal position of it. I would assume between the 2.5 piping.

[audirs]

i personally have a 3" turbo back exhaust. 3" downpipes, to 3" cat back. non res, no xpipe, into 2 vibrant performance mufflers(3" in and out). its a tad raspy but thats the price i paid for a really free flowing exhaust. its by no means a quiet exhaust. its deep and loud. at around 3k rpm in any gear its almost silent. once you go WOT it sounds awesome. in my opinion, it depends on your goals. if you never intend to go stage 3, dont bother with a 3" imo, 2.5 would suffice. if your gonna run 22+ psi, id go free flowing and large as possible

hope this helps

[pit viper]

i personally have a 3" turbo back exhaust. 3" downpipes, to 3" cat back. non res, no xpipe, into 2 vibrant performance mufflers(3" in and out). its a tad raspy but thats the price i paid for a really free flowing exhaust. its by no means a quiet exhaust. its deep and loud. at around 3k rpm in any gear its almost silent. once you go WOT it sounds awesome. in my opinion, it depends on your goals. if you never intend to go stage 3, dont bother with a 3" imo, 2.5 would suffice. if your gonna run 22+ psi, id go free flowing and large as possible

hope this helps

^ Close to my plans.

[wofman]

you're a wild man Audirs! (don't worry, Wan -- we get along fine)

Didn't realize ASP made A6 downpipes, never mind 3" (AWE starts 3+, tapers to 2.5)

[TWINTURBOA6]

Do you know what you are talking about?

A custom setup not only sounds awesome but will give great flow.

You'll spend 1500+ on name brand and my 500.00 exhaust will sound better ;)

Do you have a sound clip? hows the interior drone noise? Please send a video if you can I want to get a new exhaust set up but I dont want to do anything except for a legitimate full exhaust like piggies and a milltek or apr CB..

[audirs]

you're a wild man Audirs! (don't worry, Wan -- we get along fine)

Didn't realize ASP made A6 downpipes, never mind 3" (AWE starts 3+, tapers to 2.5)

lol, yea the arent specifically made for the a6. they are s4 downpipes, so they sent me the pipes with no secondary cats connected. the place you take it to, to get custom work done, will be able to weld in the cats for you and make it work for the car. if i wasnt getting custom work done, id get a set made for the a6 so i can just bolt them up, and bolt up watever cat back.