Michael_D

After bothering folks for months, I ended up with the B&B PRT's. I had modified OEM mufflers. ARH 1 7/8" headers, QM550 cam, ported intake. Nothing too radical.

I wanted a set of mufflers that wouldn't wake up the entire neighborhood when I start the car at 4:30 to go to work. Lack of vacuum at start up put the exhaust baffles to the open mode with the M2W mod. I also wanted the car to sound a bit less like straight pipes, a bit lower, but still sound mean at WOT.

Out of curiosity, I took some sound level readings before I swapped the mufflers out. The meter is a digital Radio Shack meter I use for calibrating my home audio gear (I'm a bit of an A/V geek). I set it to C weight and slow response (same setting I use for my home audio calibrations).

First thing I realized is that these cars are louder than one might imagine. I was pretty surprised.

I did not take any reading with the OEM mufflers other than the car sitting in garage. I didn't think about doing this till it was too late and it was raining when I thought of it.

All measurements were with the meter at the same location. The car was in the garage with the door open and the rear bumper about six feet from the door opening. I'm sure the car being in the garage added some resonance and my 'testing' was hardly scientific. It's just an interesting comparison for those who might be curious.

Cold start, meter in the car, windows up: mod'ed mufflers, valves open - 102 DB. PRT's, same conditions: 98 DB.

Idle, meter in the car, windows up: Mod'ed mufflers, valves closed - 87 DB. Mod'ed mufflers, valves open: 94 DB. PRT's - 90 DB.

Idle, meter 24" off the floor, 42" back from tips: mod'ed mufflers, valves closed - 96 DB. Mod'ed mufflers, valves open - 104 DB. PRT's - 101 DB.

Idle, meter at the hood scoop: Mod'ed mufflers, valves closed - 85 DB. Mod'ed mufflers, valves open - 93 DB. PRT's - 93 DB.

I also took the meter with me for a road trip with the PRT's installed. At 60 mph in sixth gear at 1200 rpm, road nose was louder than the exhaust and this I found surprising. I got a consistent 94 DB's. At about 1500 rpm, there is a slight drone, but it didn't give me a migraine like the mod'ed mufflers did. SPL was right at 100 DB.

Spirited blasts with rpm between 3500 and 6000, the meter pegged out at 110 DB and was having too much fun to mess with it much. Sufice to say, they are louder'n hell. Louder than the modified mufflers. They do sound much better though. Very muscle car like. Very deep, nice rumble and that deceleration popping you get, but again, not metallic sounding. More of a boom than a pop really.

After an hour playing around with the car (within the boundaries of the road rules and laws of course), my ears were not terribly happy with me. If I ever had an opportunity to road race this car for an extended period of two hours or more, I'd definitely wear hearing protection. As cool as it sounds, it's definitely loud enough to cause some hearing damage if you're at or near red line much.

Not sure if I'm going to keep the PRT's or not yet. They are louder than I was expecting. It just goes to show you really can't get a good reference listing to audio clips. Hell, my ears are still popping.

If I had a video cam, I'd take some footage, but it wouldn't do anyone any good anyway so I'm not terribly motivated to do that.

Moral of story, don't buy an exhaust because you like how it sounds on a video clip.

u1arunit

Thanks for taking the time to post this info. I wish there were more good info threads like this on here.

Antonio1988

Great thread and thanks!

Uncle Meat

When I was performing some sound-proofing on my car I too measured the interior noise levels using my trusty Radio Shack db meter.

Measured with no accessories running.
Interior db @ 1500RPM's or 70MPH with NPP closed = 78db
Interior db @ 1500RPM's or 70MPH with NPP open = 88db

This is with stock exhaust only mod is M2W.

U.M.

sammyv

Thanks for posting! Wearing a helmet on the track will block out some noise.

Michael_D

Ya, I spose a helmet would help. That slipped my mind entirely. I ride modified snow machines in the winter and dirt bikes in the summer and always were a helmet.

This winter, when the roads are too slick for the car, I'm gutting the interior and sound proofing the car, along with swapping out the stereo system.

I also weighed the two different mufflers and forgot to mention it.

Stock muff's - 25.2 pounds ea
PRT's - 22.2 pounds ea

FrankTank

I have the PRT's on my car too, and your DB readings make sense to me. At idle the modded mufflers (open mode) are about the same as the PRT's in DB.. but I think the PRT's really shine under hard acceleration, they have a very cool tone/sound to them. I also like the idle of the PRT's better than the modde mufflers, and that is the main reason I switched to PRT. Could not stand the tractor sound the modded mufflers made.

The PRT's DO drone too in case anyone is wondering, they drone pretty good at the sweet spot of about 1500 if you are in the throttle... once you hit about 1700rpm they get quiter and are fine. IMO the modded mufflers almost droned worse than the PRT's.

Michael_D

Ya, they drone a bit, but it's not nearly as bad as the mod'ed mufflers IMHO. I too like the tone at idle, as well as cold start. All the raspy-ness is gone. Wide open they friggin roar.

Which tips did you go with Frank? I went with their round tips and was surprised how much larger they are then oem. I'm still undecided if I like the new look. I definitely do not like the fact that they are tack welded together and are going to be a real bitch to keep polished. That was just a bone headed move on B&B's part. They should have left a gap to at least get a rag in-between them.

FrankTank

Yea I went wtih the Round Tips and I really like them, because like you mention they are a good deal larger. I am not sure why they welded them that way, will have to figure out a way to keep them clean. The Adams polish works really well...that's what I used on my C5 when I had the PRTs on that car.

Over all I am very happy with them.

vertC6

Any updates with the PRT's? Did you stick with them?

Jasil

wrong thread

Michael_D

So far.... I'll more than likely move to the Akra's though. These are louder than I would like.

iwantaz06now

Hey there I have a 2012 Z06 oem exhaust on my heads and cammed LS7. I find this system has the lovely popping, but at very low rpm's it doesn't sound really deep. It's almost anemic. Are the prt's deeper in sound at lower rpm's too? Do you feel the prt's drone less than the oem's open? If you still have the prt's I'd be interested in buying them

briancb1

PRT's are awesome. I have them, zero regrets.

Deep muscle car sound.

Michael_D

Oh ya, definitely deeper tone from idle to WOT. They do not drone much really. Less than modified OE's with the flaps open.

I'd sell them if I could only figure out what to move to. I have found out the Akra's are pretty loud too.

iwantaz06now

What about the fusion gen 3's?

Michael_D

This probably sounds silly, but I just don't like the look of the Fusions. I'd rather not see the mufflers, just the tips. I'm most likely going to move to the Borla Touring. I would have already if they had better looking tips.

iwantaz06now

Heya I'm not really a big fan of the tips on the Corsa system either. When your ready to sell the prt's please put me first in line
Cheers!

Ekliptix

I love my PRTs on my Z06 (stock plus filter). I'm suspect there'd be more drone with headers and high flow cats.
For anyone wondering, here are a couple vids to hear it.

iwantaz06now

This video got me excited about the prt's: