[tscdennab]

So I removed my secondary cats a few weeks ago (I already had the primaries removed) and Oh My God...the exhaust became loud as hell and it had a mad rasp, you cannot imagine how bad it sounded. Between 1800 and 2000RPM, in neutral or under load, it sounded like a lot of metal parts were grinding very loudly against each other. Basically like running open headers. Drone was not existent though thanks to the BMW Performance Exhaust.

First I replaced my OEM catless downpipes (cats replaced with pipe) with Macht Schnell 3" coated downpipes. I couldn't feel any improvement in performance or in sound, although maybe the rasp moved a couple hundred RPMs lower in the rev range. The downpipes fitted absolutely perfectly and the ceramic coating looks extremely good. The welds are also perfectly done, I am very happy with them. For $610 coated (I got a deal but it's not hard to get such a deal from MS), I think these downpipes have the highest quality/price ratio. I highly recommend them.

But what about the rasp ? I immediately ordered a pair of Vibrant 1792 resonators, and I welded them where the secondary cats used to be. I honestly didn't expect a big improvement because they are quite short (12") and straight-through inside and they couldn't possibly improve such a bad rasp and such a loud sound. Wrong ! The rasp is 100% gone and the exhaust is much quieter, identical or less loud than when I had all the cats installed ! It's absolutely incredible how a pair of $45 straight-through resonators have such an enormous effect on the exhaust note and loudness.

Conclusion: I am extremely happy with my setup. The BMW Performance Exhaust + Macht Schnell catless downpipes + Vibrant 1792 resonators produces deep, drone-free, rasp-free and not too loud sound while maintaining the performance of a fully catless setup.

Below you can find some pictures and a video of the sound.

[cn555ic]

That's the same location I installed my vibrant resonators too!! It is truly amazing how these resonators gets rid of the rasp!

[tscdennab]

Some more driving thoughts: the car definitely pulls better especially over 3500RPM. I would say I might gain about 15hp or maybe even more from the 3" downpipes (I had 2.5" before) and secondary cats removal.Dyno on Monday...we shall see

[Trojan4evr]

sounds great. I really like it.

[Tzu]

That does sound great! I've always wondered about that whistle noise as the engine winds down though, it seems very common. Or is it just a trick the camera plays?

[tscdennab]

Originally Posted by Tzu

That does sound great! I've always wondered about that whistle noise as the engine winds down though, it seems very common. Or is it just a trick the camera plays?

Thanks. The whistle noise is real, but it's not so loud in person and only present when car is in neutral.

[Mr. 5]

Resonators take away high pitched sounds such as rasp.
They don't do squat with drone.

[only1]

Sounds good. Any chance you can get some drive by video id like to hear it at part and full throttle driving.
Did the resonators take away any of the exhaust note? I have ar catless downpipes with the bmw pe and i dont want it to change i just want to remove the secondary cats.

[tscdennab]

Originally Posted by only1

Sounds good. Any chance you can get some drive by video id like to hear it at part and full throttle driving.
Did the resonators take away any of the exhaust note? I have ar catless downpipes with the bmw pe and i dont want it to change i just want to remove the secondary cats.

I was in your situation exactly. I had BMW PE and catless downpipes and then replaced the secondary cats with straight pipe. OMG. After you remove the secondary cats you will notice that the exhaust will become at least twice as loud, with an extremely bad rasp which wasn't apparent with the cats on. When you start the car the metal sound is unbelievable. You NEED the resonators. They will put you back where you were when you had all the cats on (including stock downpipes), as far as loudness. Maybe a tad louder. It will be less loud than your current setup, maybe 20% quieter. The sound detail is preserved (minus the rasp), but the camera cannot record sound properly to show it.

I bought the resonators from eBay, just type "vibrant 1792" and select the cheapest price. There is a very slim chance to do a drive-by, I don't have anyone to hold the camera (gf is sick and I don't really hang out with friends)

[only1]

Thanks man.

[bulldog_yyc]

got this same setup installed today. Resonators were key to get rid of rasp with catless DP. Exhaust sounds mean, raw but civilized, no rasp and barely ANY drone on the highway (6MT). Thanks for the insight into this - very happy I followed a similar path.

[tscdennab]

Originally Posted by turkish335

got this same setup installed today. Resonators were key to get rid of rasp with catless DP. Exhaust sounds mean, raw but civilized, no rasp and barely ANY drone on the highway (6MT). Thanks for the insight into this - very happy I followed a similar path.

[bulldog_yyc]

Originally Posted by tscdennab

dude thank you for posting up the video and pics etc. The video sounds awesome, but in person, does it no justice at all - sounds amazing. Perfect setup - thanks again for your recommendation and initial post.

[i2iSTUDIOS]

wow that sounds great!

[99three]

That sounds good. I may do the same with my AR DP's and Bastuck exhaust. I'm wondering if this set up yields a bit more hp numbers?

[wren57]

Can you please get a flyby or some in cabin video?

[tibra1]

Originally Posted by Mr. 5

Resonators take away high pitched sounds such as rasp.
They don't do squat with drone.

+1

[PeteW84]

Sounds good .

[bulldog_yyc]

Originally Posted by wren57

Can you please get a flyby or some in cabin video?

Ill try to get some videos this weekend

[marvel48]

Can we get more Catless Downpipe to Resonator instead of Secondary Cat videos please?

[geterdone]

Did you just use the stock mid-pipes, cut the cats out, and replace with resonators?

[thebigragu99]

Sounds great !! Sorry to jack the thread I'm selling 2 brand new vibrints like these for $90 shipped in the box still!!Pm me lmk people thanks!!