AA Track Pipe installed; now custom exhaust ideas?

[321eurotuner]

Installed the AA track pipe over the weekend on my 95 m3 (obd1 mid pipe was terrible.) noted a pretty big difference in the top end power. now thinking of doing a custom exhaust for the catback portion. single 2.5 inch pipe? or keep the dual 2.25's? I want to try to keep some of the back pressure, but keep the ideas or comments coming please. Anything is helpful. (I am tuned for the full exhaust)

-Zach

[Volf]

Any plans for F/I?

[pbonsalb]

Just buy a direct fit used aftermarket exhaust. Why hack up the AA midpipe or kludge and adapter out of a hacked stock exhaust? Plus, a big single pipe is louder than two twins, though the rear muffler seems to be the part of the system that does the most for the noise. Choose yours carefully if you go custom. I ran an Ireland replica USA spec Supersprint, a USA spec B&B, and a Euro Supersprint. The B&B was louder than the big Euro SS.

[gk325is]

I have a AA track pipe and a custom magna flow with two 2.25 pipes, it is loud when I get on in but is pretty quite at idle. I actually went muffler first then trackpipe and I felt that the idle was more quite with the track pipe then with my stock cats. I will try to find a video with the sound.

[arthothezilvian]

Look into an x-pipe. Reduces drone and doesn't kill torque vs. a cat delete.

[pbonsalb]

He already bought and installed the AA track pipe. An X pipe needs to go in the midpipe area. The AA trackpipe takes the two header secondaries and dumps them into a single 3 inch pipe to a muffler and then runs twin pipes out the muffler to the rear exhaust. Not ideal, but it works.

[jeremy5000]

If you want loud get the UUC System U... UUC is having a sale this week.

[321eurotuner]

all ideas considered, and im not hacking up the aa mid-pipe. the idea would be using the stock cat-back portion and cutting it there..using the flanges to bolt and un-bolt the exhaust. and yes, goin sc'd in the future

[CodyLTR]

I have the AA headers, track pipe and UUC RSC36 cat back and below 4.5k it is very timid but after that it screams. Zero drone too. I haven't personally experienced other UUC exhausts but have heard good things about them. If you've spent the extra coin on a track pipe why go cheap on the cat-back?

[Bimmer Man]

If you want loud get the UUC System U... UUC is having a sale this week.

UUC has a sale EVERY week. Same deals, different name. I'd know because they spam the hell out of my inbox.

[breakfast]

staying n/a.
stick with 2.5"

3" if you are going to boost it.

though for the time being without boost youll notice huge low end grunt loss.

[jeremy5000]

UUC has a sale EVERY week. Same deals, different name. I'd know because they spam the hell out of my inbox.

Yea I get an email from them like everyday now but I got 4 17x9 Dforces from them for under $900 and I got my UUC System U from them for $300 so I can't complain

[Uraharasan]

staying n/a.
stick with 2.5"

3" if you are going to boost it.

though for the time being without boost youll notice huge low end grunt loss.

What power level/boost level would the single 3" become optimal?

[pbonsalb]

This is a subject of debate. Bimmerworld sells a 3.5 inch exhaust for the S54 cars that have 330 hp from the factory. BMW equips those cars with twin 60 mm piping (about 2.375 inches) from the factory, which works out to a total area that is bigger than a single 3.0 pipe.

However, plenty of people have made 500+ rwhp with a single 3.0 exhaust. With a turbo, though, boost can simply be raised to counter inefficiencies, within limits. For example, the single 3.0 might need 16 psi to make 500 whp, but a single 3.5 might need only 15 psi to make 500 rwhp.

On a turbo car, the size of the exhaust after the turbo can be as big as possible without negatively affecting the torque curve. On an NA car, you are probably trading low end for top end power when you go bigger, at least until you are as big as necessary to fully support the power you have.

I personally think that a twin pipe exhaust with an X pipe in the midpipe and stepped headers is best for a daily driven naturally aspirated car. I might settle for just a redesign of the stock parts in the same diameter or I might go up just 1/8 inch, depending on how much power I had.

My 99 M3 is turbo now and I use a single 3.5 inch exhaust. It was previously supercharged and I tried replica USA supersprint headers with real USA supersprint midpipe and B&B rear exhaust, but eventually moved on to larger RMS long tube headers with real Euro mid and rear exhausts and thought the bigger system was the better choice for the 400+ rwhp.

Unfortunately, the only stepped headers currently available for the E36M3 are the very expensive Kromerkraft. Stepped headers have been shown to yield good gains on the S54 according to dyno testing by European Car. They add low to midrange power as well as top end power.

[321eurotuner]

hmmm...once again all ideas and comments considered. i know uuc has great sales plus their exhaust sounds amazing. ill prolly look into them or go custom with a single 2.5 pipe? no plans for turbo over sc'd, so even with a 2.5 pipe it should be able to support the power as there isnt a turbo to spool.

[Volf]

UUC has a sale EVERY week. Same deals, different name. I'd know because they spam the hell out of my inbox.

This ^

[Relax]

I'm N/A and I run a single 3" cat back exhaust, with plans of making it 3" header back in the future.

[EisnerRacing]

I have an AA mid (no cats) with a B&B love the look and the sound is very aggressive..

[321eurotuner]

went with UUC System U!

[jeremy5000]

You won't regret it, it should sound amazing with the aa track pipe.