Supersprint headers + Custom 3" Exhaust

[3002 tii]

Plan is to go headers + custom 3" exhaust on my Z4. Anyone else here plan on doing something similar whether it be Supersprint or Active Autowerke? I'm wondering what resonator and/or mufflers others are considering. As of now I'm planning on doing single 3" with resonator in the middle finished off with a turbo style muffler. Hopefully this will keep me below 90dB so I won't have issues at certain tracks and I won't go deaf during the long drive to/from the track.

Here's a video of Vorshlag's custom 3" exhaust on their E46 330ci, basically headers + resonator delete + Flowmaster Hushpower 3" muffler.

http://videos.smugmug.com/TechArticl...il/master.m3u8

Edit: March 28, 2015

Still not happy with the rasp in the higher revs. Going to swap out the resonator but in the meantime this is how she sounds:

Edit: April 30, 2015

Exhaust is done and sounds fantastic. Swapped out the Vibrant 1794 for a 1142. Final layout:



Less rasp with the new resonator, has a nice deep rumble:

Edit: July 12, 2015

Muffler has broken in nicely over the last month or so

Edit: July 20, 2015


Ended up selling my diffuser and while at it decided to look for a new tip. At the time I couldn't find a set of stainless steel dual 3" tips for less than $100 manufactured in USA. Most of the stuff on eBay is from sellers from China. My luck would have it that I found a race shop who started offering dual slant cut double walled tips. Decided to take a chance and very happy with the results:

[chris82]

Originally Posted by 3002 tii

Plan is to go headers + custom 3" exhaust on my Z4. Anyone else here plan on doing something similar whether it be Supersprint or Active Autowerkes? I'm wondering what resonator and/or mufflers others are considering. As of now I'm planning on doing single 3" with resonator in the middle finished off with a turbo style muffler. Hopefully this will keep me below 90dB so I won't have issues at certain tracks and I won't go deaf during the long drive to/from the track.

Here's a video of Vorshlag's custom 3" exhaust on their E46 330ci, basically headers + resonator delete + Flowmaster Hushpower 3" muffler.

http://videos.smugmug.com/TechArticl...il/master.m3u8

I like it. Where are you getting the custom exhaust done?

[Kgolf31]

I'm coming out of my headers, 200 cell secondaries and a resonator to no muffler.

I need to get a dB reading to see what I come in at. But I need to be under 100 dB at 50'

[3002 tii]

Originally Posted by Kgolf31

I'm coming out of my headers, 200 cell secondaries and a resonator to no muffler.

I need to get a dB reading to see what I come in at. But I need to be under 100 dB at 50'

Mind posting a video again? How's drone?

[Kgolf31]

Originally Posted by 3002 tii

Mind posting a video again? How's drone?

Drone isn't bad. Really reverberates between 2-2.5k

80 mph cruise is extremely peaceful though. 70 mph might be annoying

[JimD]

I think going a little larger for exhaust makes sense. How big to go, however, should consider the sizing of the exhaust of the highest hp n52, I think it is in the X5. The outlet from the muffler is larger than I've seen people doing here, if my memory is working (based upon RealOEM information). If 3 inch is equal to slightly larger than this, I think it will work well. If it is more than slightly larger, I would scale back. Less back pressure seems like it would always be good but our engines are pretty complicated and it could either not help or even be negative if you go too far.

[chris82]

Originally Posted by JimD

I think going a little larger for exhaust makes sense. How big to go, however, should consider the sizing of the exhaust of the highest hp n52, I think it is in the X5. The outlet from the muffler is larger than I've seen people doing here, if my memory is working (based upon RealOEM information). If 3 inch is equal to slightly larger than this, I think it will work well. If it is more than slightly larger, I would scale back. Less back pressure seems like it would always be good but our engines are pretty complicated and it could either not help or even be negative if you go too far.

3" is plenty for a ~260hp car. In the Mitsu evo crowd it's very common to do a full 3" single exhaust, and those cars push 400 hp in some cases. HPF makes a 3" single exhaust for the 135i, and again, they are making 300-400hp, almost 100 more than ours in some cases.

[Kgolf31]

So, just something to note.

I downloaded a dB meter on my iPhone. Isn't exactly calibrated instruments but close enough.

Out of a toll booth yesterday next to concrete barriers I decided to go WOT and see what I'd read with the phone sitting basically on the window, window down with the mic facing the outside (but not being outside to avoid wind playing any contributing factor).

I recorded a Max of 99 dB. Once again not something to take to the bank but worth mentioning IMO

[andrey_gta]

I have a 3" no secondaries or resonator. Its great with the 135i muffler, but for when I do headers I will have to do something to make it civil

Originally Posted by Kgolf31

Drone isn't bad. Really reverberates between 2-2.5k

80 mph cruise is extremely peaceful though. 70 mph might be annoying

System sounds real nice, hopefully its a good sound to daily with considering headers..

Can you link me to your exhaust set up. 200 cell cats sound like that is non OEM
Thanks!

[Kgolf31]

Originally Posted by andrey_gta

I have a 3" no secondaries or resonator. Its great with the 135i muffler, but for when I do headers I will have to do something to make it civil




System sounds real nice, hopefully its a good sound to daily with considering headers..

Can you link me to your exhaust set up. 200 cell cats sound like that is non OEM
Thanks!

I love DDing it. Honestly when you're cruising at steady state the system is quiet.

OEM Secondary Cats are 200 cell. So it's a OEM system from headers back, thru the resonator and no muffler.


Eventually I'll be fabricating 100 cell cats (Minimum per SCCA STX Rules) and doing a LTW muffler to a dump pipe somewhere in the middle of the car to reduce weight.

[TheSt|G]

Originally Posted by JimD

I think going a little larger for exhaust makes sense. How big to go, however, should consider the sizing of the exhaust of the highest hp n52, I think it is in the X5. The outlet from the muffler is larger than I've seen people doing here, if my memory is working (based upon RealOEM information). If 3 inch is equal to slightly larger than this, I think it will work well. If it is more than slightly larger, I would scale back. Less back pressure seems like it would always be good but our engines are pretty complicated and it could either not help or even be negative if you go too far.

Less back pressure is always better, but losing velocity for the sake of pipe width isn't good.

[MarkkyyMan]

Originally Posted by chris82

3" is plenty for a ~260hp car. In the Mitsu evo crowd it's very common to do a full 3" single exhaust, and those cars push 400 hp in some cases. HPF makes a 3" single exhaust for the 135i, and again, they are making 300-400hp, almost 100 more than ours in some cases.

Apples to Oranges comparison. You are talking about two turboed cars vs a NA car.

[chris82]

Originally Posted by MarkkyyMan

Apples to Oranges comparison. You are talking about two turboed cars vs a NA car.

Yea but wouldn't any car producing 300+hp/tq be pushing out more exhaust gases than a NA car producing 260? Turbo forces more air in, more burnt fuel, more gases or am I missing something

[3002 tii]

Slight update:

After waiting many months:




Unwrapped:



AA off-road tune uploaded before leaving car with the shop. I was just told stock headers are out and SS headers bolted in fine. In fact the fitment was perfect and no need for any o2 extenders.



As I mentioned in other threads, the Supersprint headers for the Z4 do not come with flanges and I was prepared for a custom job. What I didn't realize was how far they headers would dump out. We may have to trim piping on the header side in order for everything to bolt up and flow. Plan to use V-bands for easy removal down the road.

[Kgolf31]

Woah, that's a long run.

Excited yet?!

[3002 tii]

Originally Posted by Kgolf31

Woah, that's a long run.

Excited yet?!

Indeed. I've already purchased the other downstream components. Fingers crossed everything will fit seamlessly as I've planned it. Hoping to have an update by Tuesday.

[andrey_gta]

@[3002 tii]
i am surprised that z4 headers are flange-less. No wonder you had about two years of searching for a solution.
So now your headers will go into a single 3" pipe with a single cat?
Will you coat the headers?
What about the exhaust, any paint/coating?

[3002 tii]

Originally Posted by andrey_gta

@[3002 tii]
i am surprised that z4 headers are flange-less. No wonder you had about two years of searching for a solution.
So now your headers will go into a single 3" pipe with a single cat?
Will you coat the headers?
What about the exhaust, any paint/coating?

More like 2 years of waiting for an alternative till finally giving in lol. But you are correct in that I was hoping for a bolt-on solution. Luckily I found a buyer for my current catback so I could justify the added cost of a new custom exhaust.

Correct, 2 into 1 single 3" but no cat. I will have a resonator in the middle and muffler in the rear. Car is rarely driven on street, only to/from track.

Headers were not wrapped nor coated.

[Taskmaster]

I...Can't wait. Can we have a dyno PLEASE?!

[3002 tii]

Originally Posted by TheAxiom

I...Can't wait. Can we have a dyno PLEASE?!

Things have been so hectic I never had a chance to baseline. So not sure what value there is doing a dyno after the mods.

BUT if there's a tri-state member here who wants to dyno his N52 (stock, 3 stage, AA headers, SS headers, tune or not) just so we can do some form of comparison, I'm down for that.

[631twentyeighteye]

Always down to get a tristate n52 meet together! I'm tired of having 1 or 2 n52's at the dyno day.. We should get one of the SC'ed guys there too if possible.

shameless 2,000 post plug!

[chris82]

I'd consider another dyno in tristate area