Hello all! I'm planning on getting a downpipe soon and I was wondering which brand you would say has the quietest sound out there. I currently only have a muffler delete, but I might put it back on when I get a new dp. My last cobalt had the ZZP downpipe and a magnaflow muffler, it was pretty loud and would get a lot attention from the police and people wanting to race. I'm not a street racing kind of person, so I love keeping my car as low-key as possible. Has anyone ever measured with a spl meter the difference in exhaust parts brands?

Thanks!

 

i have the hahn catless and full hahn exhaust and at an idle and easy on the throttle sounds like your stock but once your really get into it you can hear it and its got a nice sound to it... i love it

 

honestly go with any catted downpipe since they are pretty much the same and then the mpx exhaust or hahn exhaust if your looking for the quietest. if your lowered mpx is your best bet since they built theres around someone lowering their car

 

Any downpipe other then your stock one is going to have some kind of rumble to it, whether its catted or not.

so your best bet would be to put your stock one back on if you dont want to bring any attention to yourself.

 

Or just put your stock muffler back on with the aftermarket DP. That's what I have, Hahn 3" Catless DP, with the stock resonator, and muffler. And it's soo quiet, you can't tell the difference between that and stock that much at all.

 

Is the LNF ZZP catted downpipe pretty quiet? I'm going to put the muffler back on when I get a DP. As it is with stock dp and no muffler, its at a pretty good noise level. What would be louder, stock dp with delete or aftermarket dp with muffler on? My only problem with muffler delete is the engine pop noise is a lot more noticeable with downshifts or what not. With an aftermarket DP do you hear these kinds of noises and does it ever resonate at a certain rpm speed and make a weird rattling noise? (my old zzp would resonate at a certain speed and make an odd noise sometimes)

 

I have the ZZP catless downpipe to their catback and its not that loud

Their catted dp to the stock exhaust is gonna be pretty quite with a little rumble to it I'm sure it will sound good.

 

The stock DP with the MD would be louder than the aftermarket DP and muffler in place.

And you can hear very quiet pops from the DP on downshifts.

I have the Hahn 3" Catless DP with the stock muffler & resonator & my boy RYRO14 has the CIA Catless DP with the MD, and his pops are loud, and they sound good.

 

I honestly think you should keep the stock exhaust on your car or just put a catted downpipe....no matter what exhaust you put its going to sound different then stock

 

You want quiet as possible.. but you have already done a muffler delete. I don't fully understand that. You will want to put you stocker back on if you put on a dp, it will make it a lot louder.

A catted downpipe on stock exhaust is pretty quiet. I put mpx exhaust on after my downpipe and it made it a bit louder, the mpx has a good rumble but isn't super loud. No where near as loud as the gmpp sport exhaust on my SS/SC. If you are after quiet it isn't hard to achieve on the TC. You could do a catted with stock or hahn exhaust and you would not have any trouble avoiding the cops, most trucks will be louder. As far as the catted downpipes go, they will all be about the same noise wise, a catless will be a bit louder and more rumbley.

 

Just buy a catless. I have a catless with a 3 inch magnaflow...and its not terribly loud unless I get on it...then I put on my "o" face.

Of course with no muffler...ehhhh. Might be a loudish and raspy.

 

Keep in mind that the turbo muffles the sound a lot. So Either way it will be quieter than your old SC/SS. Nobody believes me when i tell them i have a 3" straight back exhaust. It's not loud at all during normal driving and just sounds nice and throaty when getting on it. Not excessively loud.

 

Check out the All You Need To Know About Downpipes sticky. There's some sound clips there. I made one of my Spun Metal Catted ZZP downpipe.

It's fairly quiet under light load / cruising and idle, but not at all quiet if you go WOT.