MBRP T409 3" Catback Review w/Decibel Readings & Video

[RaptorRacing]

Hey guys;

I know there are a few threads out there with MBRP reviews, so if the mods chose to merge this that's cool by me. I was looking for a post/thread where someone had some decibel readings off their MBRP and couldn't find one so decided to do it myself. I've said it other threads and I'll reemphasize here; this thing is LOUD. I'm not new to aftermarket exhausts and certainly don't have "old man" standards when it comes to noise. Since my first car in 93 to this current car I haven't had one car where the exhaust stayed stock, and to me this is loudest and most irritating exhaust I've had. I didn't have the resources to test my theory but I'm 99% certain that this system is louder on the inside than others are on the outside. I've done plenty of exhaust product testing, unfortunately won't have time to do that to the MBRP as it's coming off on Wednesday.

Some say it's "tolerable" , to each his own...the resonance as it stands is brutal but it's a steal for a 3" system so appreciate that there is a market for this. My testing is usually more involved but I kept it nice and simple this time as I couldn't borrow an assistant due to time constraints. Don't mind the rubber bands, I had to MacGyver a way for the meter to be held by my phone mount.

Decibel reading on a quiet street, engine off, radio volume off, windows up:

Decibel reading on a quiet street, engine on, radio volume off, windows up:

Decibel reading on a quiet street, engine on, behind car 5ft up:

Highest Decibel Reading; 5th gear about 3300rpm:

I actually got a decibel reading of 106, I was trying to be fancy and take a video of the decibel readings to show that I'm not making this up but the number wasn't readable. So I just stuck to pictures, unfortunately that will have to do. There is no point (in my opinion) of taking video in the car to show how loud it is, no camera can capture resonance and quantify so the person watching the video can understand what it's like. I will say this; if this was a track only car I can't imagine a better system...the sound to me is incredible. I suppose if I decided to hack it up and put in a resonator it could be better, but that would defeat the purpose of buying a bolt in system.

Here is a video that I "found" of some guy with the exact same car, driving "in mexico", with the exact same mods. I know it says Toronto at the end of the video but I can assure you this wasn't me. It's hard for the GoPro to capture it but I personally LOVE the backfiring it, like i said...i'm not opposed to cool car noises, just not ones that sound like a jackhammer is on your head:

[video=vimeo;144404343]https://vimeo.com/144404343[/video]

Oh and for reference:

 

[twolf]

Make sure your exhaust isn't hitting on the little mid chassis brace. Mine was hitting right there and causing some iiiiiiinsane resonance.


I honestly don't feel that it's that loud. Definitely not as loud as a rock concert...

 

[RaptorRacing]

Yup...had it in the air and inspected it twice as to me it just made no sense how loud it was. We're going to inspect it one last time before I take it off on Wednesday to make sure it wasn't rubbing. Sometimes the only way to tell it was rubbing is to take it off completely and inspect the pipe/chassis. Up in the air it's not rubbing anywhere that we can see.

Probably perks of a 3" system on a car with not that much clearance, which is why I'm guessing some find it "ok" and some want to launch it of a cliff!

 

[Hijinx]

I have the aluminized version and there is no way it's as loud as a rock concert in my car, ever. Even when the external opens up... I think it's an issue with the material used.

 

[RaptorRacing]

The reading of 102 decibel's isn't something that lasts more than a second, unfortunately I just don't have a way to capture this on video to show the meter as I'm driving. It has a min/max setting, for the most part even at the 102 decibel reading it's hovering at VERY high 90's then peaks when the resonance gets bad. In 1st to 3rd gear the highest rating was about 95, but 4th-6th gear under load is when it gets loud.

Anyway, trust me not complaining as for the most part I really love this system...all good as there are other options.

 

[Siestarider]

My latest experiment swapped the Vibrant resonator out of the "muffler location" and into the location of the MBRP resonator, then added Vibrant straight through muffler to tail. Made the resonation between 3000 and 4000 rpm worse, not better. It is actually worse now than the original MBRP confuguration right out of the box was.

I have researched "T" 1/4 wave resonator tubes, and mass moment arms, and sound deadening options. I don't want to give up on 3" with Cyborg being built, but what I have now not is not livable on the street.

My rear seat delete actually quieted the car with stock exhaust on, now its part of the resonance problem. Cabin is literally unbearable at full throttle between 3 & 4K rpm. But great sound everywhere else.