Technical DIY Exhaust Options? What sounds the best?

[IQraceworks]

I think I’ve finally decided to do something with the stock exhaust on my 07’ 335i. The oem exhaust with the flapper mod sounds ok, but I’d like it to sound a little better. I want it a little louder, but I still want to keep it “tight” sounding like the oem exhaust if that makes sense. I don’t like the raspy, tin-can sound of a straight pipe system. Ideally, I want it quiet like stock on the highway and cruising, but get aggressive sounding when you are hard on the throttle. It would be nice to also get the exhaust flowing better for when I end up upgrading turbos….Not sure I believe it, but most of the turbo manufacturers say you need to upgrade your exhaust to extend the life of them.

I’ve done my own custom exhausts for all of my other vehicles over the years, and even though it’s a little time consuming…it’s a lot cheaper then buying a “kit” from someone (most of the time), and you can really tune the sound to your own taste.

I’ve got all the tools in my shop that I need to build the exhaust (welder, bandsaw, etc, etc)…I just need to figure out the “hardware” side of how I want to set it up. I currently have ARM DP’s, but the rest of the exhaust is stock.

So, here are my options I’m thinking about.

1. Leave the stock exhaust in tack, just swap the secondary cats for Vibrant resonators (#1792)
2. Same as #1, but also swap the mufflers out for Vibrant “Ultra Quiet” resonators (#1141)
3. Buy the VRSF “Race” Exhaust and install a Vibrant resonator (#17970) in the system
4. Do “PE MOD” on stock mufflers, and swap secondary cats with Vibrant resonators (#1792)
5. Make a full 3.5” or 4” single exhaust from the DP’s back…with resonators in place of the secondary cats.

What other options am I forgetting? Suggestions?

 

[NoGuru]

I think the ones you mention are all good options and the way you should go. The only thing you did not list was a valvetronic exhaust or dumps.

It really depends on what you want but from the items you listed I bet you already know what you are going to go with.

I have DP's, vibrants in place of secondary's and IS "PE" mufflers and love the sound. No rasp, pretty quiet until you get on it a little.

 

[Torgus]

PE mod sounds great. Highly recommend it for starters and it is cheap to DIY or buy the real thing.

A 4" would be ideal.

 

[Subwoofer]

So I have a downpipe on my 335I, which already made it sound better on stock. I then bought a muffler delete, which in my opinion was great. But I was getting huge amounts of vibration or drone in the cabin.

I decided to do the PE mod and it’s perfect, sounds amazing on WOT, and is not loud at cruising.

 

[MattGu40]

i went with 1 and welded vacuum cutouts between rear diff and mufflers. Had the bmw PE installed before but was too loud for my liking. Cops at home can be very annoying i have put back original muffler

 

[Jern54]

i went with 1 and welded vacuum cutouts between rear diff and mufflers. Had the bmw PE installed before but was too loud for my liking. Cops at home can be very annoying i have put back original muffler

Same over here, love the idea to control the amount of sound with just one press on the remote control.

 

[IQraceworks]

I'm thinking about just starting with removing the secondary cats and replacing them with vibrant 1972 resonators. That should at least get rid of any restrictions in the exhaust. If it needs more volume after that I can always do the PE muffler mod. The resonators on amazon are around $50 each.

 

[tisdrew]

I had #4 on my old car and loved it.

 

[IQraceworks]

I had #4 on my old car and loved it.

#4 what?

 

[turbohugh]

Factory exhaust is heavy. I lucked up when I got my car, someone had a full Borla catback. Sounds amazing and fitment is great, and the tips say 'Borla' .. See if you can find a set , IMHO all the exhaust that merge to a single muffler ruin the sound. Stick with dual, and if you retain the secondary cats/resonators it wont be droning ..

A short vid.. I was testing a new camera.

 

[NoGuru]

#4 what?

Probably how you listed it.

"
1. Leave the stock exhaust in tack, just swap the secondary cats for Vibrant resonators (#1792)
2. Same as #1, but also swap the mufflers out for Vibrant “Ultra Quiet” resonators (#1141)
3. Buy the VRSF “Race” Exhaust and install a Vibrant resonator (#17970) in the system
4. Do “PE MOD” on stock mufflers, and swap secondary cats with Vibrant resonators (#1792)
5. Make a full 3.5” or 4” single exhaust from the DP’s back…with resonators in place of the secondary cats."

 

[filhotran]

I had #4 on my old car and loved it.

did the resonator swap make a big difference? i currently have the PE mod but want to make my car a tad louder without muff delete or downpipes and sacrificing emissions cuz i’m in cali

 

[ShocknAwe]

Love my 3.5 mids on 3" everything else. Have a secondary cat and resonator and muffler. It's loud but not stupid and quite civilized if I remain in like kind.