Magnaflow Catback

B6/7 S4/RS4
#1

So I finally got off my lazy ass and bought and installed a Magnaflow catback on my S4. I gotta say it is a very different sound and I kind of miss the staccato blat the oem exhaust with fully gutted cats had. I’m assuming the smoother sound from the Magnaflow is a function of the x-pipe and not the resonators?

Edit to say that after a day of close to 200 kms of driving it seems to be breaking in and has a bunch of its old bark back. But my original question stands; the x-pipe reduces the staccato nature by mixing the pulses?

#2

Yes, To keep the gurgly/burbly sound you need either a true dual system or an H pipe. The X pipe or “crossover” smooths the exhaust out

#3

Drive it for a while let the mufflers break in and you will get a differnet tone and the noise level changes.

#4

Well As ChrisK mentioned it did indeed break in a bit but is still only marginally less boring that when it went on. If I’m going to have a V8 muscle car I would preferre that it is able to sound a bit bonkers when asked to. I spoke to a local exhaust fab guy ( www.higherarcing.org ) and he suggested that my dislike of the sound stems not from the resonators or cross over but from the Magnaflow mufflers and that I’d be better off ditching those over the resonators. I would need to still be able to sneak off my street in the morning without being a total dick to my neighbors ( I leave for thw office most days at 6 am) I’ve looked around for some videos of a similar set up with no avail and am not sure how loud this could turn out being.

Ditch the cans: Good idea / Bad idea?

#5

Do hooker maxflow mufflers. On paper they are really good. Almost as quiet as stock when cruising but really aggressive when you step on it, seems like what you are looking for. 91gl was going to run them before he stopped his project. And they are cheap.

#6

Hey JPO, where did you get the Magnaflow exhaust from? I’m local to you and I see you driving quite a bit downtown. Plus the car sounds good :smiley:

#7

Hi. I got it from hottexhaust.com. Easily the best price for Canadian buyers. Thanks for the compliment; I hope to soon have it sounding gooderer. The more I think about ditching the mufflers the better I feel about it. There is a s5 in the same parking garage as me and they have just center resonators and it sounds just right, nice and badass.

You must be an early riser if you see my car downtown a lot; I’m parked before most people start their commute.

#8

Bangoman is this where you got your mflow?

Jpo
care to share the price after all fees and shipping etc?

#9

I got mine from performancepeddler.com using the coupon code “audipipes”. IIRC It was about $720 (US) shipped to my door, including Steve/Dalton/QE2’s cut. No doubt I love my Magnaflow. Stock-ish suits me fine. But saki’s old S4 and bora’s S4, both 2.5" DP, no cats with FI exhaust, sound better. But much louder and aggressive!

#10

Huh. Mine was 799 to my door. When I priced the one from performance peddler at the time I figured it would come in at a bit over 800 with taxes, duty and shipping etc.

#11

I guess they raised their prices. Plus 5% for you vs 13% tax!

#12

Bangoman do your piggies have the main cats intact?

As an aside to this, how much extra jam (if any) would I get in going 2.5" catless downpipes from fully gutted piggies?

#13

When Saki and i went to mexico last year, we made a few highway pulls from bottom of second to top of 3rd ish gear iirc.

Both cars were exact same setup minus he had 2.5 catless DP’s and i had piggies (still had the main cat though)

He had 1/4-1/2 car lenght on me me when we pull off the throttle. If i were catless all the way that might have been more on the dead even to 1/4 car lenght range.

#14

yeah, I’m a HUGE believer in piggies. They work extremely well. Part of it is the fact that OEM main cats are excellent. I would take piggies over a catted aftermarket downpipe any day of the week personally.

JHM made a 2.5 MPH bump in trap speed when they went from piggies to 2.5 catless downpipes (audirevolution.net/quartermile) but frankly I only saw about 1 MPH difference in trap speed. That was over 20-30 runs on each setup, so the sample size for me data was good. The piggies will certainly hold you up a bit and I know it’s tempting to want that extra amount of power but the added noise levels + the fact you’re no longer going to pass emissions in any of the testing states wasn’t really worth it to me.

Piggies FTW on the B6/7.

If however you want every inch, don’t have to worry about emissions and want a car that is rip-snorting loud and will scare the fuck out of anyone walking down the street with just a blip to 3000 RPM with the clutch in as you roll by, 2.5 catless are pretty incredible. They were definitely a lot of fun.

#15

I have all 4 cats gutted, would 2.5" catless down pipes be materially louder?

So from the above, any performance gains would be nominal.

#16

Yep main cats intact. Saki’s old piggies in fact. BTW I had an emissions test last week and there’s next to nothing coming out the tail pipe so thanks sak for selling me a pair of mint cats lol. The tester was pretty impressed.

God knows how many miles are on them but they should be good for a while yet.

#17

I wish I could get away with running without cats. I love the sound of a gurgling V8, especially with the right cam profile.

But, on the other hand, I do like to be incognito sometimes. It’s one of my favorite things about a stock RS4. Most people think it’s just a regular family sedan (including the overly-friendly police officers).

#18

I still think it’s the resonators that make it too smooth. I was lazy/motivated so I pulled a muffler section off but only one. Sound files:

2 mufflers

http://soundcloud.com/jp-oh/2-mufflers

1 muffler

http://soundcloud.com/jp-oh/1-muffler

They sound the same, just one is louder. :frowning:

Edit: I guess the on muffler one does sound a bit more coarse (in a good way)