I’m sorry actually now I’m more confused, I am not familar with the term hogpipe.
Can you break it down for me in terms of each side? Or tell me if this is correct…
the exhaust starts with the exhaust manifold, which connects to the downpipe and thin the down pipe I am guessing has the precat o2 sensor which is followed by pre cat. then there more piping followed by the main cat and another o2 sensor and then more piping and then the muffler ?
and then it would be the same on the other side, assuming thats correct which i doubt, cuz i dont understand where the hogpipe comes in?
Lout Jnr’s dps
exhaust manifold -> pre-cat -> piping down -> post cat -> catback exhaust
There o2’ in each cat and 2 dp’s per car, thats why some people have 2 massive cats per car and others have 4 cats.
Check out my exhaust album and my description should make sense. If it doesnt I can mock up the exhaust manifold and dp to make it clearer as they are sitting on my bedroom floor at the moment.
So after installing both DP’s I will still have 2 cats on each side. If they are going to affect the tune I would like to look into HFC’s if they aren’t expensive. Cuz if they need to be gutted I am guessing that will basically be like having straight pipes which again I’m guessing that would not be a sound I would like because I have never heard a car with straight pipes to date that I thought sounded good for my personal tastes. So anyways what options do we have?
Hogpipes= the larger cat where it is actualy two cats in one.
Piggiepipe= The Pre cat.
Both Dps have two cats. The hogpipes just have them jammed up top to make what looks like one large cat. The Piggie pipes have two cats there just seperated. One is up top and the other one is several feet back.
The seperation of the cats would make more sense for performance. One large cat would most likely kill power to some degree
I think you guys are all missing what the Count means by “hogpipe”.
He’s calling it the “Hogpipe Mod”
The 4.2 S4’s did what was called the “piggie pipes” mod which was to gut the out the material in the precat.
So the "hogpipe mod “would be to gut out the material in our main and only cat but still leave it in place. This should give us a good bump in performance but not nearly as big of one as if we were to get something like 2.5” aftermarket DP’s
And this is why I hate the state if California and its God damn emissions. At least ill have a little increase thanks to this hog-pipe mod… Ahhh 2.5 days till ill have a little write up on all the mods for you guys. Try and make some videos too for you all.
On a side note; you guys think it’d be a pain in the ass to invest in the dp’s and every 2 years swap them out for my cats to get smogged?
yes the 3.0 cat is so big its a hog. Its bigger then a piggie and its straight hogging the performance from the car.
The DP’s Im working on will have removable cats so you can be catless and when its time to go do emissions testing you can just put a set of cats in.
As for performance. Ill let keaton update the thread on monday. Lets just say the tune adapts and once the hogs were removed the car woke up. Stock with no cats the car wasn’t really that much faster.
From a tune perspective the tune is limited by the cats. So the removal of them has resulted in a dramatic gain. We removed the cats on 916’s car and made sure to do some testing.
We tested for sound change, performance change and the difference between the stage 1nc (stage 1 tune and the nc=no cats) and the stage 1 just a chip. We log the cars to do so. On one of the logs keatons stage 2+ 1.8T just happened to be next to it and we just happened to have a camera running to see. Anyone interested in seeing what the results were?
Any chance we could please get an update on the DP’s ?
And sorry if this is a dumb question but is there a cat back setup available yet? cuz I wasnt sure if we could use the S4 setup or what the deal was with that. And if we can use the S4 setup, does anyone know an estimate of how much it is with labor assuming Dp’s at the same time are installed. Sorry I’m just curious if its something I maybe could afford.
And what could I expect from the tune with the dp’s and cat back?
^I think the consensus was the Magnaflow 2.5" catback is the best option price & performance for the 3.0 guys. It’s about $640 with coupon discount. And when you have 2.5" catless dp’s, it’ll match up almost perfect I would imagine. There’s no reason to get it before you get dp’s though, b/c you’ll be paying to make it fit 2.25", then paying to make it fit your new setup.
Doing tune + catless + 2.5" catback. . . that’s gonna wake yall up big time! So to help on pricing (and this is total guesses as I haven’t talked to JHM one time about the 3.0) would be $500 for tune, $~600 for catless dp’s, $650 for catback, $~300 for DP install, $100 to install catback and maybe modify anything to fit better.
I have a local exhaust guy that put on my magnaflow 14851s and talked to him recently about upgrading the full exhaust to match the dps of 2.5" piping. I already have the mufflers on, I have the magnaflow x pipe ready for install and he would do the custom piping for me. His quote was from 230-270 dollars for install and all the piping. He does quality work for a good price. I would look around at some good exhaust shops and see what kind of deal you can get. 200 for the mufflers, 75 for the x pipe, then 250 for the full exhuast. Total of 525 installed and sounding like a beast. Saving you a couple hundred dollars or so.
^^^
Yeah I think I’d personally go more of something like this, or like B6JoeS4 did to his old 3.0 (because I’d also like to have resonators)
Just get custom 2.5 piping done to an X-pipe, then a set of resonators, to a set of Magnaflow mufflers. In the end it’ll prob come out just a little cheaper than getting the new in box catback
Been there guys, done that. I now have a F.I. exhaust for a reason. Parting it together either:
A) Will be more expensive in the long run (sure was for me) or
B) Will be significantly less quality (unless a very high price premium is paid to a master fabricator)
The first problem you start off with is your fabricator is going to use all crush bends. So this means your nice 2.5" exhaust is now nothing more then a 2.25" exhaust (wherever you smaller restriction is means that’s your max flow), but due to the rest of the piping being 2.5" you’ve now got bottle neck and a good mandrel bent 2.25" would actually flow better most likely. Having the piping change diameter does more then just reduce the amount of gas that can get through, it distorts the pulses and you no longer have that nice vacuum effect pulling the following pulse out to increase velocity. These are KEY factors to a NA exhaust as you’re trying to scavenge for every little bit you can as the motor is the only thing pumping the air out (rather then f.i. pumping it through).
So you say, no problem, I’ll buy some mandrel bent 2.5" piping to keep everything true. Good thinking, that’s what I did too! Then you run into fact that:
A) This just jumped up your price by a good $50-150+ dollars depending on how many of the bends you warrant buying. I bought 2 45degree bends from summit and I think that was around $65.
B) Then, how good are the welds? Not as in “will they break or leak or rust” but "How smooth is the interior of the piping? When I saw the JHM headers, Count had me run my finger over the outside of each weld, and you could barely feel a difference in piping, it’s simply amazing. . . It’s extremely important the interior is the same way! (exterior doesn’t matter in that since, but the point is the interior has to be like that as well) Most exhaust shops are just concerned with making a solid weld all the way around, but if some overflows inside, no big deal. So again, if each exhaust puff from a cylinder is a pulse that is constantly pushing outward on the piping, whenever it hits irregular surface changes (i.e. shoddy welds, crush bends, piping etc) the pulse is disturbed and begins to loose shape. This means the pulse begins to spread out and thus you have less vacuum effect to pull the pulse behind it. The name of the game is always velocity.
So at this point (once you buy some mandrel bent piping) you’re almost to $600 if not well over after everything is said and done. Maybe you don’t like the magnaflow mufflers and that’s reason enough to go your own route. But I just feel it’s my prerogative to inform people as much as I can to prevent them from following the same footsteps I did. I spent probably $900+ in 1.5yrs of tinkering with different custom setups to the point where I ended up with a full 2.5" exhaust with a shallow x-pipe and mandrel bent piping. Lets just say when Count saw it in person. . . he was less then impressed. We even went as far as to find a B6 F.I. to install on my B7 during the s/c install that weekend b/c he felt a LARGE amount of my issues from timing being pulled that I recorded in logs were due to the exhaust. Afterwards, my timing was right in check.
So coming from someone who walked down that road extensively, my opinion is it’s not worth it on this car when there’s a good option out there for so cheap. If you really wanted to do something kind of custom, the best thing to do is buy the magnaflow and swap in a shallow X pipe to help with scavenging and reduce drone ( I could even sell mine probably if someone wanted it). Like I said, I spent close to if not over a thousand dollars on the custom catback approach, and now not 1 single piece from all my experimentations is still on the car and I’ve gotten zero cash so far for any of those parts.
While I see where your coming from and that whole situation sucks. I am debating on resonators myself, I don’t want it too loud.
My exhuast guy will be using all manderal bends and that is all included in the price. Quality whise, I have seen hundreds of cars that my guy has done full exhuast systems on paper and have seen quite a few in person while at his shop. This guy does top quality work and stands behind his work. I could just be naive or you could have just had a completely bad experience or a little of both.
On the resonator part, if I were to run just the x pipe to the mufflers how loud would it be? I don’t want a race car sound, but I do want something more aggressive than normal.
^I understand where you’re coming from, and there ARE quality people out there who can make a quality exhaust, it’s just few and far between. I would sincerely double check about the use of all mandrel bit parts, but it sounds like your guys is more of a custom fabricator then an exhaust shop. I just don’t want everyone thinking they’ve found a good guy to make them an exhaust and think it’s going to be comparable or better then what’s currently available.
As far as resonators, for the most part, they really just clean up the sound, but don’t really decrease volume. There are some that certainly diminish volume, but for the most part they are there to take out the rasp and give it a more appealing tone. My F.I. has 14" resonators, and JHM has certainly heard just about every setup of the F.I. setups, and they explained it to me the same way as I just did. However, right now I don’t have my mufflers on (having the shop realign them today with my new bumper) and HOLY SHIT is the car loud with catless headers + x-pipe + 14" resonators. It’s twice as loud as it’s ever been before, and I had electronic cutouts. So I can say with resounding confidence, the resonators do little to decrease volume haha. Right now the car sounds beastly as all get out and it literally sounds like a GT race car, but as much as fun as I thought getting a second set of piping from the resonators back made would be, I think it’s just too loud for anything other the 1/4 strip. But seeing peoples faces would be great!
So yes, resonators are a great way to clean and refine the sound without loosing any of the sound you still desire and I recommend them to most people.
I also did get the short end of the stick with my custom build. But I worked with 2 different shops over the stages of the build, and I thought I followed everything to the T, but it’s fine print (or moreso what isn’t printed) that makes the real difference. I even used to advise people to follow the same steps I did. . . then Count set me straight and really took the time to explain the importance in all the details to make it the best you possibly can.
