[iturbo_bmw]

I had this exhaust mod done years ago and I loved it. Keeping the flap on meant you could easily switch between quiet and loud with the jb4. It really opens up past 5k rpm. Sounds like a completely different car up there and sounds crazy in a good way

If anyone needs a stock pair of mufflers with tips and flap in tact, LMK. I have a pair for sale!

[BimmaBwoy335i]

Originally Posted by Yyzsw

I got a OEM bmw performance exhaust for sale if anyone is interested

Im interested. PM asap please.

[thurstonhowelltha3rd]

Less cat pipes down, x pipe, secondary delete, 2 vibrant 1792s, pe mod both mufflers(1 perforated pipe replaced with straight pipe in each muffler), 4 inch tips

[course]

Originally Posted by WhiteFury

Actually. I am working to make sure that it wasnt co-incidence. I currently made another muffler and just finished installing it. I wanted to make sure it was 100% before I go spilling beans to which may be nothing more than a mess.

Forgive me for trying to provide accurate results instead of guesses. I am the only one who has a modded factory muffler that replicates the PE exhaust. I just wanted to make sure so I have held off until today where I have finsihed a second muffler that sounds the exact same.


Here are the results. I can confirm as of 1 hour ago when I finished the second exhaust muffler that my method is consistant.


Step 1. cut the top of the muffler. Both of them.

Step 2. remove packcing on the perforated pipe (passenger side)

Step 3. replace passenger side perf pipe with straight stainless pipe.

Step 4. cut the canister out of the driver side. This WILL require cutting of the other side. I used a plasma cutter and only took 1 minute. (there is no packing on this side its inside the canister. No need to open it.

Step 5. replace driver side with stainless straight pipe.

Step 6. remove approximately 20% of the packing in the H/Y cross pipe on each side. (DO NOT CUT, OR TAMPER WITH THESE PIPES! AS ITS THE ONLY THING THAT TRULY KILLS THE DRONE! THIS IS THE SECRET EVERYONE HAS WANTED. SILLY YES BUT TRUE)

Step 7. Put back 75% of the packing in passenger side, pack tight all around.

Step 8. take the 25% from the passenger side muffler and the 20% from the two center pipes and stuff nicely on the driver side muffler so they are all equal.

Step 9. weld everything shut.


The car below 2500 rpms doesnt make enough pressure to generate complete straight trough exhaust and a good portion will get trapped in the cross pipe. Thus having the perforated pipe and packing stop drone and rasp.

At high rpms the pipes act as a bridged straight pipe. The packing in both mufflers stop the drone, rattle and help silence other things as well.


Sound is tricky. The only way to stop drone is to physically absorb it. Drone is like dead zones in a recording studio in a sense. So the rockwool is actually absorbing the drone from the staright pipes.

If you remove more than I have recommended you risk more drone, and the exhaust wont be much louder.

I will have pictures later.

I just did this on my passenger muffler and the sound is perfect! Thanks for the guide!

[mweisdorfer]

Originally Posted by thurstonhowelltha3rd

Less cat pipes down, x pipe, secondary delete, 2 vibrant 1792s, pe mod both mufflers(1 perforated pipe replaced with straight pipe in each muffler), 4 inch tips

What were your numbers on the Dyno?

[mike_o]

Originally Posted by mweisdorfer

What were your numbers on the Dyno?

Late to the party, but the video's description says 430whp.

BTW, I have a 335is (factory PE), FBO (incl. catless dp), and recently also Pure stage 2 turbos. The car was loud and droney before the Pure turbos, but I was surprised how much louder they made it.

I'm considering adding extra/custom mufflers, but I doubt if there's room for it anywhere...

[GnomeChild]

Sell me your M Performance exhaust I really don't want to buy stock mufflers for this mod and end up with merely an imitation of the real thing for the same price

[lomon98]

Hi,

this has probably been mentioned in this forum before but I was just wondering what mod would be better to make my exhaust louder (and not ricey ofc). As PE mod and catless DPs (vrsf I guess?) cost more or less the same (300 bucks or so) I was wondering which one would you guys recommend to do first (or only). Maybe I'll end up doing both in the future, but I wanna do just one first.


Thanks!

[Jaronbwall]

Originally Posted by lomon98

Hi,

this has probably been mentioned in this forum before but I was just wondering what mod would be better to make my exhaust louder (and not ricey ofc). As PE mod and catless DPs (vrsf I guess?) cost more or less the same (300 bucks or so) I was wondering which one would you guys recommend to do first (or only). Maybe I'll end up doing both in the future, but I wanna do just one first.


Thanks!

Don't waste your time going straight pipe, muffler delete, or buying anything expensive. If you're capable with tools you can DIY the PE mod. It's an easy project. Pay a shop to weld everything back up. Throw on cat-less DP's and you'll love it. If you straight pipe you can enjoy the sound of rassssp and droooone. It's terrible if you daily long distances.

My exhaust is almost identical to the above video. It sounds deep, throaty, pops/bangs with MHD tunes, and no drone. The only cost was my time, 1792s ($130), welding labor ($100), x-pipe ($25), and used DP's ($250). Good luck finding a full exhaust for $500 with DP's. It's impossible. Cheers.

[oVeRdOsE.]

catless downpipe (VSRF) + OEM mid pipe + real Performance Muffler = worst sound ever.

(I still have a OEM Performance muffler to sell, if someone want to try)

It sound shit, it's a shame for a L6 engine.


There's few option, but I'm going single exit. A bit the reason why the N55 sounds better.

[lomon98]

Originally Posted by Jaronbwall

Don't waste your time going straight pipe, muffler delete, or buying anything expensive. If you're capable with tools you can DIY the PE mod. It's an easy project. Pay a shop to weld everything back up. Throw on cat-less DP's and you'll love it. OR you can enjoy the sweet sound of rassssp and droooone. It's terrible if you daily or drive long distances.

My exhaust is almost identical to the above video. It sounds deep, throaty, pops/bangs with MHD tunes, and no drone. The only cost was my time, 1792s ($130), welding labor ($100), x-pipe ($25), and used BMS DP's ($250). Good luck finding a full system exhaust for $500. It's nearly impossible. Cheers.

Yeah I am afraid I don't have the tools, but if I were to get the DP I think I would buy a jack at least, it doesn't seem to be a difficult DIY job. My fear is that the PE mod won't be much noticeable alone (and wo catless DPs)...

[Jaronbwall]

Originally Posted by lomon98

Yeah I am afraid I don't have the tools, but if I were to get the DP I think I would buy a jack at least, it doesn't seem to be a difficult DIY job. My fear is that the PE mod won't be much noticeable alone (and wo catless DPs)...

All you need a grinder, Sawzall, and like 3 exhaust parts from AutoZone. You don't want it super loud. That's the point. The N54 sounds bad straight piped w/ cat-less DPs. YouTube videos never show the DRONE while driving.