billyboy47

personally, i would try to find a cheap set of npp pipes before drilling holes in my car. its a neat trick, only down side is if there is drone there is no way to control it. i have the npp system in mine and i love the fact of being able to go mild or wild. but, thats just my opinion.

BWF07

I did this mod well over a year ago. I have long tubes ARH and the catted x-pipe and the A6 transmission. Yes there is some drone, but at in 6th is is hardly noticeable.

As far as a cheap NPP, the best I found was $450 plus the MTW kit you need. This cost me the two bits and the patch material Sure you can spend the $400-$600 on a used set on NPP, or go the big route with cat backs, but for now this mod is fine with me, and judging from the amount of post on the topic, I bet a lot of others have done it.

v26278

There's drone and then there's DRONE. I have a slightly detectable drone from this mod, but barely enough to be called drone. It's not like you get from SLP's or Magnaflows, where you brain vibrates inside your head. No passenger has even commented on it or noticed it. The best description I can give for this mod is that your Vette will sound like a stock Vette should, nothing obnoxious or loud, just a nice V8 rumble.

Look at tit this way, if you hate the ultra-quite stock sound, before you invest in after-market, give this a try. If you don't like it, your stock mufflers weren't worth anything any way so toss them and install NPP's, Corsas or Bullets or whatever you like.

Z0HS1CK

Well thats what i mean.

If the drone is bad, it'll give me a reason to just get axlebacks or NPP's. I'm sure i'll be able to sell my non NPP with the muffler mod to someone here.

Basically i want my car to sound like what our cars sound like with the NPP valves OPEN. I want to replicate that sound, without going NPP i don't have to. I don't care about idle sound, that i don't mind if it stays silent. I just want noise when i get on the throttle. Right now there is none. My brother's stock miata has more exhaust note than my car lol

rkm812

I just bought a 2011 C6, and like a lot of you guys I am wondering how to get a little more growl out of the tail pipes. Nothing loud, but a little more than what the stock pipes are offering. I was a Harley guy for years and cored out the stock pipes on more than just a few. It always resulted in a nice deep thump with a bit of a hollow tone to it. It will be interesting to see if anyone comes up with an answer to the stock pipes. If not, it looks like I will have to pop for a Flowmaster or the like.

Z0HS1CK

So weather is looking great and I wanna do this mod soon.

My question is since the fiber glass material is to "deaden" the sound, will it make sense to just drill a hole under the actual muffler in the middle Where the fiberglass is and just use a pick or screwdriver etc to pull The fiberglass out?

loudvolvo

maybe this picture will help you. this is a muffler from an '05

cuspid

Why not stick a 2 ft long drill bit down the tail pipe and go thru the pipe.?

Markallamerican

I drilled another hole towards the front of the car, see pic above, pulled the fiberglass out and patched it up

400HPZ51

I did this mod yesterday. 1in holes in both sides of the pipe.

Pros
Pretty easy to do. Took about an hour including jacking and clean-up time.

Cons
Very little change in the sound. A little deeper at idle but not very much.

Guess I'll start saving my pennies for a Corsa Sport system.

Z0HS1CK

What about acceleration?

Was there any noticeable difference?

400HPZ51

Are you asking if the car accelerated better (made more HP/TQ)? If so, I couldn't tell any difference.


Are you asking about change in sound tone/sound volume during acceleration?
I was only able to drive around the neighborhood a little before I had to put it back in the garage. I wasn't able to accelerate hard during that time but I did a few 0-30mph half throttle blasts. Maybe a 10% increase in sound volume. Tone was about the same as stock. I'll live with it for a few weeks and see if I like the change or not.

Update: I've driven the car for a few days now. I'd say the volume increase is more around 20% across the board. I'm liking the sound a bunch, especially for the price. For those looking for a little more volume over stock, this is a great mod. As said before...this is how the car should have sounded from the factory. I'm really on the fence now as to whether or not to get a axle-back system.

Z0HS1CK

I'm about to do this mod. Which side of the muffler did you drill?

When looking at the tips straight on, did you drill the left side of the left muffler and the right side of the right muffler?

Or the inside portions of both mufflers?

I bought an 1 1/4 drill bit. Just gonna go right through the damn thing lol. Then patch it up with a piece of sheet metal and screws.

I don't wanna spend 1300 bucks on an axleback. I already have long tubes but i can't/don't want to install it because i don't wanna void my warranty. My car is still basically brand new with 7k miles so and being NON NPP, the car is QUIETTTTT. I can't hear a damn thing. lol

I don't want the car to be noisy at idle. If anything, i want my sound to only come when i step on the throttle. That's the only thing i'm going for with this mod.

400HPZ51

Right side of the right muffler...left side of the left muffler.
On the right muffler the hole is at about 5 o'clock. On the left muffler the hole is at about 7 o'clock.

Orion2011

Just the ones that came with the dual mode exhaust. If you had that you probably wouldn't be posting this question to begin with.

Orion2011

Not my video and I have not tried this.

Z0HS1CK

Thanks for the info.

What i did was install long tubes with a borla axleback lol

Sounds IN-EFFIN-CREDIBLE!

SS60

I'm with you. Tried the cheap way. Did the mod yesterday, very easy but I am not impressed at all. It's a different sound but imo not better. Also makes my head hurt after a few minutes. Not worth the small effort.

Rojo8

What's the difference between Magnaflow 14335 and 14336?

SS60

I posted earlier. I did the mod yesterday and absolutely hate it. After driving for about 10 minutes if feels like my ears are going to pop. I don't even want to drive the car until I get some different mufflers. I looking for some used OEM's now.