Exhausted by Exhaust

[StiffNeck]

Hello, I would sure appreciate some advice from E85 enthusiast. The wife finally relented and let me get an 07 Z4 3.0i with the N52 engine. The age of the car allowed the mod bug to bite and after having everything serviced first and new rubber on I had an aFe intake and the 3 stage manifold upgrade done topped off with an Active Autowerke's tune. Next was AA's N52 performance headers which became a headache since they were not designed for the Z4 chasis. My bad, but I got to know Karl Hugh very well though ( great guy!) and we were finally back on the road with another tune and several adaptations. Now I am considering either a new muffler or a header back exhaust. Could really use some advice from experienced fellow E85 people. I like the Angry Cop angle but wonder if it would be too loud with the AA headers which sound great by the way. The simple route would be an Eisenmann muffler but......

thanks in advance!

[3002 tii]

Catless headers plus any aftermarket catback is going to be drone city. It took me so many iterations on my old n52 with custom components to eliminate drone.

[wdb]

Eisenmann makes an N52 Z4 exhaust. Wallet buster but their stuff is known for excellent sound. I had their Sport cans on my Z4MC and they were a delight.

[StiffNeck]

So it sounds like trying anything fancy will become another headache with the drone huh? The sound now is magnificent to my ears with the AA headers so maybe I should simply get a nice set of tips as that was what got me started thinking of a new exhaust anyway.

Do you think the Eisenmann sport muffler would sound good with the Active Autowerkes headers, or is that something that would be a gamble? Really appreciate the input guys. Thanks.

[StiffNeck]

Dear 3002 tti, I apologize if I am breaking rules here, but my newby status to BMW and this forum has made it clear to me that you are a very well experienced library of good information.

I appreciate you letting me know that my AA headers that deleted the first set of cats will compound excessive noise if I add any cat back exhasut. In your opinion does that include cat back systems like the Scorpion which not only complies to fitment of my 3.0i facelift Z4 but has cats included? Also, if I simply go with a super sprint or eisnenmann fitted muffler will I be okay?

Sure wish I had more knowledge in cars like most everyone on this forum.

[Piper1]

Originally Posted by StiffNeck

Also, if I simply go with a super sprint or eisnenmann fitted muffler will I be okay?

Sure wish I had more knowledge in cars like most everyone on this forum.

It’s a good place to learn about your car .
Regarding supersprint you’ll need either their Y pipe section or fab one up. Their system reduces 2 pipes to 1 larger going into their muffler where you can band clamp the eisenmann in on the existing pipes once muffler gets cut off. On my 03 with the M54 I went racing dynamics headers and full supersprint post headers. Can be pricey but watch for sales to save a bit if you’re going more than just back half with supersprint.

[3002 tii]

Originally Posted by StiffNeck

Dear 3002 tti, I apologize if I am breaking rules here, but my newby status to BMW and this forum has made it clear to me that you are a very well experienced library of good information.

I appreciate you letting me know that my AA headers that deleted the first set of cats will compound excessive noise if I add any cat back exhasut. In your opinion does that include cat back systems like the Scorpion which not only complies to fitment of my 3.0i facelift Z4 but has cats included? Also, if I simply go with a super sprint or eisnenmann fitted muffler will I be okay?

Sure wish I had more knowledge in cars like most everyone on this forum.

Grabbed random image off google but this is your exhaust after the headers. Dual pipes with secondary cats -> resonator -> muffler. SS and Eisenmann are really pricey considering it’s just mufflers only. Scorpion never heard in person but I don’t like how their name is engraved in the tips.

End of day the headers provide best bang for buck in terms of performance. None of those catbacks will yield any real additional gains since the only real bottleneck left are the secondary cats and it’s not like the stock piping is inefficient.

From my experience there isn’t much middle ground when it comes to drone. You figure those catbacks were designed assuming most users would keep factory headers. Throw in catless and it tips the scale to drone city.

If you really want incremental more volume, I’d consider going custom if you have any decent exhaust shops nearby. I’d do a 2-into-1 Y pipe right where the resonator is and pick a quality aftermarket muffler with tips of your choice. You’ll save weight with the merge and it should still cost less than SS or Eisenmann. Or alternatively, just chop out the resonator and secondary cats - that alone might get you what you’re looking for.

[StiffNeck]

You guys are the best. I really appreciate your knowledge and past experiences and the wonderful photo of an E85 post facelift exhaust. I have seen drawings but it is nice to actually see one.

Lots to contemplate and hey, I keep forgetting to just be grateful for the thrill driving a roadster with the top down can be. Especially if there are some curves involved. I can easily see why so many do track their cars or rather build a car for the track. Thanks again.

[DiscoJax]

I recently added new catless headers from Racing Dynamics but kept the rest of the exhaust OEM and I couldn't be happier.

There's A little drome right around 2k RPMs but it quickly subsides. The OEM exhaust sounds great when I open it up!