Anyone swap an MBRP muffler for another using the cat back system?

Got an MBRP cat back system and the resonance is bothering me. The noise isn't crazy, it's the resonance going up hills, etc. I picked up the system stupid cheap so no regrets.

I'm considering swapping out the MBRP muffler for another brand and using the MBRP cat back. That way I can reduce the resonance and keep the 3' cat back system. I found a couple of promising options, but this one looks like the best thus far:

https://www.magnaflow.com/products?partNumber=13743

It's an XL series, which is supposed to be designed to reduce resonance and it's a 3 chamber design. If it works, I would basically have a Magnaflow cat back system for under $300.

Any thoughts on this? Anyone done this before and have any tips?

 

Went ahead and ordered the Magnaflow. I guess we'll see what happens....

 

Let me know how well it works out. I bought the Same cheap mbrp system and have been wondering about the same thing.

 

Will do. I don't think it would work as well with the DCLB configuration, because you'd have to get an exact fit for the MBRP muffler dimensions. You have to cut the pipe down for the DCSB wheelbase. In my case, I didn't trim as much from the front pipe because I had the idea in the back of my head for a replacement if I didn't like the sound. Glad I left the extra inch and a half or so.

 

Yeah, I cut the whole 13 1/4 they recommended. Im probably going to roll with the same pipe at least till the muffler gets warn in. The high rev sounds drive me nuts though.

 

any updates on the sound with the magnaflow muffler? I just installed the MBRP last night and I am NOT a fan of the resonance.

 

Not yet - the Magnaflow just arrived today. Hoping to get it installed in the next few days.

 

3"? That is way too big for this truck. My 419rwhp Trans Am has a single 3" exhaust.

 

Its only 3 inches from the cat back, it cant hurt it.

 

Not to be a smarty pants, but more than one post above indicate something is hurt.

 

I blame the muffler for that not the pipe.

 

Borla lists their 2016-17 kit with a 2.5" dia. pipe. They usually never increase pipe diameter because you want to keep the respective back pressure while eliminating restriction in the muffler. Too little restriction in the system will effect your low end but you'll see better HP in the high end range.

 

Got impatient and installed the Magnaflow last night. Only one commute of 30 miles of highway, but I can report a decrease in the resonance. I'd guess maybe 50% less? At cruising (highway speeds or not) there are no issues at all. When the transmission kicks down or you floor it, it's still on the louder side, but quieter than the MBRP muffler. I'll drive around with it for a week or so to decide. I will say that the Magnaflow is an upgrade for sure.

I'll also say that the fit might have been a little challenging if I didn't leave that extra inch of pipe when I trimmed the system, since the MF muffler is shorter than the MBRP.

 

I just ordered a

$166 Magnaflow 12279 : 3"/3" Inlet/Outlet, 5x8x24" Oval, Stainless Steel, Satin Finish

Magnaflow 12279 muffler to try and tone it down a little bit. The specs on the muffler are 5"x8" oval and the muffler is 24" long (30" overall") so it should be a fair bit quieter than the MBRP. I'll have to get a little creative to make it fit I think but it shouldn't be a big deal. I have a DCLB so I have a little extra space back there anyway.

I honestly don't feel any power difference at low RPM with the 3" cat-back and maybe a teeennnyyyyy bit of improvement in the top end.

I think that the point of restriction is the flange going in to the cat-back so changing anything from there back will have minimal impact on performance. My main reason for getting this system is to improve ground clearance and cut down the chances of smashing my tailpipe in to the fender anyway, so I'm not here to chase every 1/2hp at this moment.